diff --git a/examples/grc/dcsk_demo.grc b/examples/grc/dcsk_demo.grc
index 8c2f048..5a14c0b 100644
--- a/examples/grc/dcsk_demo.grc
+++ b/examples/grc/dcsk_demo.grc
@@ -1,188 +1,330 @@
-<?xml version='1.0' encoding='ASCII'?>
+<?xml version='1.0' encoding='utf-8'?>
+<?grc format='1' created='3.7.11'?>
 <flow_graph>
   <timestamp>Sun Oct 28 19:39:04 2012</timestamp>
   <block>
-    <key>chaos_gen_logi_map_f</key>
+    <key>options</key>
     <param>
-      <key>id</key>
-      <value>chaos_gen_logi_map_f_0</value>
+      <key>author</key>
+      <value>Julien Olivain &lt;julien.olivain@lsv.ens-cachan.fr&gt;</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>window_size</key>
+      <value>1280, 1024</value>
     </param>
     <param>
-      <key>seed</key>
-      <value>0.1</value>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>description</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(61, 88)</value>
+      <value>(8, 4)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_deinterleave</key>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>hier_block_src_path</key>
+      <value>.:</value>
+    </param>
     <param>
       <key>id</key>
-      <value>gr_deinterleave_0</value>
+      <value>dcsk_demo</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>max_nouts</key>
+      <value>0</value>
     </param>
     <param>
-      <key>type</key>
-      <value>float</value>
+      <key>qt_qss_theme</key>
+      <value></value>
     </param>
     <param>
-      <key>num_streams</key>
-      <value>2</value>
+      <key>realtime_scheduling</key>
+      <value></value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>run_command</key>
+      <value>{python} -u {filename}</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(233, 75)</value>
+      <key>run_options</key>
+      <value>prompt</value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>thread_safe_setters</key>
+      <value></value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>DCSK Demonstration</value>
     </param>
   </block>
   <block>
-    <key>gr_float_to_complex</key>
+    <key>variable</key>
     <param>
-      <key>id</key>
-      <value>gr_float_to_complex_0</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
-    <param>
-      <key>vlen</key>
-      <value>1</value>
-    </param>
     <param>
       <key>_coordinate</key>
-      <value>(388, 75)</value>
+      <value>(272, 4)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>dcsk_samples</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>50</value>
+    </param>
   </block>
   <block>
     <key>variable</key>
     <param>
-      <key>id</key>
-      <value>dcsk_samples</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
-    <param>
-      <key>value</key>
-      <value>50</value>
-    </param>
     <param>
       <key>_coordinate</key>
-      <value>(226, 10)</value>
+      <value>(176, 4)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>samp_rate</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>100000</value>
+    </param>
   </block>
   <block>
-    <key>chaos_dcsk_mod_cbc</key>
+    <key>blks2_packet_decoder</key>
     <param>
-      <key>id</key>
-      <value>chaos_dcsk_mod_cbc_0</value>
+      <key>access_code</key>
+      <value></value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>n_samples</key>
-      <value>dcsk_samples</value>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(278, 189)</value>
+      <value>(928, 276)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>blks2_packet_decoder</key>
     <param>
       <key>id</key>
       <value>blks2_packet_decoder_0</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
       <key>type</key>
       <value>byte</value>
     </param>
+    <param>
+      <key>threshold</key>
+      <value>-1</value>
+    </param>
+  </block>
+  <block>
+    <key>blks2_packet_encoder</key>
     <param>
       <key>access_code</key>
       <value></value>
     </param>
     <param>
-      <key>threshold</key>
-      <value>-1</value>
+      <key>bits_per_symbol</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(919, 226)</value>
+      <value>(232, 372)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>blks2_packet_encoder_0</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>byte</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>pad_for_usrp</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>payload_length</key>
+      <value>512</value>
+    </param>
+    <param>
+      <key>preamble</key>
+      <value></value>
+    </param>
+    <param>
+      <key>samples_per_symbol</key>
+      <value>2 * dcsk_samples</value>
+    </param>
   </block>
   <block>
-    <key>variable</key>
+    <key>blocks_deinterleave</key>
     <param>
-      <key>id</key>
-      <value>samp_rate</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>blocksize</key>
+      <value>1</value>
     </param>
     <param>
-      <key>value</key>
-      <value>100000</value>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(148, 10)</value>
+      <value>(192, 136)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>blocks_deinterleave_0</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>num_streams</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
   </block>
   <block>
-    <key>gr_file_sink</key>
+    <key>blocks_file_sink</key>
     <param>
-      <key>id</key>
-      <value>gr_file_sink_0</value>
+      <key>append</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
@@ -192,180 +334,343 @@
       <key>file</key>
       <value>output.txt</value>
     </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(1096, 268)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>id</key>
+      <value>blocks_file_sink_0</value>
+    </param>
     <param>
       <key>type</key>
       <value>byte</value>
     </param>
+    <param>
+      <key>unbuffered</key>
+      <value>True</value>
+    </param>
     <param>
       <key>vlen</key>
       <value>1</value>
     </param>
+  </block>
+  <block>
+    <key>blocks_float_to_complex</key>
     <param>
-      <key>unbuffered</key>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1090, 226)</value>
+      <value>(344, 136)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>blocks_float_to_complex_0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
   </block>
   <block>
-    <key>blks2_packet_encoder</key>
+    <key>blocks_packed_to_unpacked_xx</key>
     <param>
-      <key>id</key>
-      <value>blks2_packet_encoder_0</value>
+      <key>bits_per_chunk</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
+    <param>
+      <key>endianness</key>
+      <value>gr.GR_MSB_FIRST</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(424, 372)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>id</key>
+      <value>blocks_packed_to_unpacked_xx_0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>num_ports</key>
+      <value>1</value>
+    </param>
     <param>
       <key>type</key>
       <value>byte</value>
     </param>
+  </block>
+  <block>
+    <key>blocks_throttle</key>
     <param>
-      <key>samples_per_symbol</key>
-      <value>2 * dcsk_samples</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>bits_per_symbol</key>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(344, 276)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>id</key>
+      <value>blocks_throttle_0</value>
+    </param>
+    <param>
+      <key>ignoretag</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>samp_rate</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>vlen</key>
       <value>1</value>
     </param>
+  </block>
+  <block>
+    <key>blocks_vector_source_x</key>
     <param>
-      <key>access_code</key>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>pad_for_usrp</key>
-      <value>False</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
-      <key>payload_length</key>
-      <value>512</value>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(217, 304)</value>
+      <value>(8, 396)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>blocks_vector_source_x_0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>byte</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>tags</key>
+      <value>[]</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>vector</key>
+      <value>map( lambda c: ord(c) , "Hello GnuRadio!\n" )</value>
+    </param>
   </block>
   <block>
-    <key>gr_packed_to_unpacked_xx</key>
+    <key>channels_channel_model</key>
     <param>
-      <key>id</key>
-      <value>gr_packed_to_unpacked_xx_0</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>block_tags</key>
+      <value>False</value>
     </param>
     <param>
-      <key>type</key>
-      <value>byte</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
-      <key>bits_per_chunk</key>
-      <value>1</value>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
-      <key>endianness</key>
-      <value>gr.GR_MSB_FIRST</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>num_ports</key>
-      <value>1</value>
+      <key>epsilon</key>
+      <value>1.0</value>
+    </param>
+    <param>
+      <key>freq_offset</key>
+      <value>1e2 / samp_rate</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(396, 322)</value>
+      <value>(528, 204)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_vector_source_x</key>
     <param>
       <key>id</key>
-      <value>gr_vector_source_x_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>type</key>
-      <value>byte</value>
+      <value>channels_channel_model_0</value>
     </param>
     <param>
-      <key>vector</key>
-      <value>map( lambda c: ord(c) , "Hello GnuRadio!\n" )</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>repeat</key>
-      <value>True</value>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>noise_voltage</key>
+      <value>0.5</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(9, 322)</value>
+      <key>seed</key>
+      <value>0</value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>taps</key>
+      <value>1.0 + 1.0j</value>
     </param>
   </block>
   <block>
-    <key>gr_throttle</key>
-    <param>
-      <key>id</key>
-      <value>gr_throttle_0</value>
-    </param>
+    <key>chaos_dcsk_demod_cb</key>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>type</key>
-      <value>complex</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
-      <key>samples_per_second</key>
-      <value>samp_rate</value>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(468, 202)</value>
+      <value>(728, 276)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>chaos_dcsk_demod_cb</key>
     <param>
       <key>id</key>
       <value>chaos_dcsk_demod_cb_0</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
       <key>n_samples</key>
@@ -375,131 +680,126 @@
       <key>n_sync</key>
       <value>2</value>
     </param>
+  </block>
+  <block>
+    <key>chaos_dcsk_mod_cbc</key>
     <param>
-      <key>_coordinate</key>
-      <value>(717, 226)</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>comment</key>
+      <value></value>
     </param>
-  </block>
-  <block>
-    <key>gr_channel_model</key>
     <param>
-      <key>id</key>
-      <value>gr_channel_model_0</value>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>noise_voltage</key>
-      <value>0.5</value>
-    </param>
-    <param>
-      <key>freq_offset</key>
-      <value>1e2 / samp_rate</value>
+      <key>_coordinate</key>
+      <value>(120, 264)</value>
     </param>
     <param>
-      <key>epsilon</key>
-      <value>1.0</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
     <param>
-      <key>taps</key>
-      <value>1.0 + 1.0j</value>
+      <key>id</key>
+      <value>chaos_dcsk_mod_cbc_0</value>
     </param>
     <param>
-      <key>seed</key>
+      <key>maxoutbuf</key>
       <value>0</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(646, 77)</value>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>n_samples</key>
+      <value>dcsk_samples</value>
     </param>
   </block>
   <block>
-    <key>wxgui_fftsink2</key>
+    <key>chaos_gen_logi_map_f</key>
     <param>
-      <key>id</key>
-      <value>wxgui_fftsink2_0</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
-      <key>type</key>
-      <value>complex</value>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
-      <key>title</key>
-      <value>FFT Plot</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>samp_rate</key>
-      <value>samp_rate</value>
+      <key>_coordinate</key>
+      <value>(8, 148)</value>
     </param>
     <param>
-      <key>baseband_freq</key>
+      <key>_rotation</key>
       <value>0</value>
     </param>
     <param>
-      <key>y_per_div</key>
-      <value>10</value>
-    </param>
-    <param>
-      <key>y_divs</key>
-      <value>10</value>
+      <key>id</key>
+      <value>chaos_gen_logi_map_f_0</value>
     </param>
     <param>
-      <key>ref_level</key>
+      <key>maxoutbuf</key>
       <value>0</value>
     </param>
     <param>
-      <key>ref_scale</key>
-      <value>2.0</value>
-    </param>
-    <param>
-      <key>fft_size</key>
-      <value>1024</value>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>fft_rate</key>
-      <value>15</value>
+      <key>seed</key>
+      <value>0.1</value>
     </param>
+  </block>
+  <block>
+    <key>wxgui_fftsink2</key>
     <param>
-      <key>peak_hold</key>
-      <value>False</value>
+      <key>avg_alpha</key>
+      <value>0</value>
     </param>
     <param>
       <key>average</key>
       <value>False</value>
     </param>
     <param>
-      <key>avg_alpha</key>
+      <key>baseband_freq</key>
       <value>0</value>
     </param>
     <param>
-      <key>win</key>
-      <value>None</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>win_size</key>
+      <key>comment</key>
       <value></value>
     </param>
     <param>
-      <key>grid_pos</key>
+      <key>affinity</key>
       <value></value>
     </param>
     <param>
-      <key>notebook</key>
-      <value></value>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>fft_size</key>
+      <value>1024</value>
     </param>
     <param>
       <key>freqvar</key>
@@ -507,132 +807,129 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(838, 19)</value>
+      <value>(728, 44)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>options</key>
     <param>
-      <key>id</key>
-      <value>dcsk_demo</value>
+      <key>grid_pos</key>
+      <value></value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>id</key>
+      <value>wxgui_fftsink2_0</value>
     </param>
     <param>
-      <key>title</key>
-      <value>DCSK Demonstration</value>
+      <key>notebook</key>
+      <value></value>
     </param>
     <param>
-      <key>author</key>
-      <value>Julien Olivain &lt;julien.olivain@lsv.ens-cachan.fr&gt;</value>
+      <key>peak_hold</key>
+      <value>False</value>
     </param>
     <param>
-      <key>description</key>
-      <value></value>
+      <key>ref_level</key>
+      <value>0</value>
     </param>
     <param>
-      <key>window_size</key>
-      <value>1280, 1024</value>
+      <key>ref_scale</key>
+      <value>2.0</value>
     </param>
     <param>
-      <key>generate_options</key>
-      <value>wx_gui</value>
+      <key>fft_rate</key>
+      <value>15</value>
     </param>
     <param>
-      <key>category</key>
-      <value>Custom</value>
+      <key>samp_rate</key>
+      <value>samp_rate</value>
     </param>
     <param>
-      <key>run_options</key>
-      <value>prompt</value>
+      <key>title</key>
+      <value>FFT Plot</value>
     </param>
     <param>
-      <key>run</key>
-      <value>True</value>
+      <key>type</key>
+      <value>complex</value>
     </param>
     <param>
-      <key>max_nouts</key>
-      <value>0</value>
+      <key>win_size</key>
+      <value></value>
     </param>
     <param>
-      <key>realtime_scheduling</key>
-      <value></value>
+      <key>win</key>
+      <value>None</value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(10, 10)</value>
+      <key>y_divs</key>
+      <value>10</value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>y_per_div</key>
+      <value>10</value>
     </param>
   </block>
   <connection>
-    <source_block_id>chaos_gen_logi_map_f_0</source_block_id>
-    <sink_block_id>gr_deinterleave_0</sink_block_id>
+    <source_block_id>blks2_packet_decoder_0</source_block_id>
+    <sink_block_id>blocks_file_sink_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>blks2_packet_encoder_0</source_block_id>
+    <sink_block_id>blocks_packed_to_unpacked_xx_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_deinterleave_0</source_block_id>
-    <sink_block_id>gr_float_to_complex_0</sink_block_id>
+    <source_block_id>blocks_deinterleave_0</source_block_id>
+    <sink_block_id>blocks_float_to_complex_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_deinterleave_0</source_block_id>
-    <sink_block_id>gr_float_to_complex_0</sink_block_id>
+    <source_block_id>blocks_deinterleave_0</source_block_id>
+    <sink_block_id>blocks_float_to_complex_0</sink_block_id>
     <source_key>1</source_key>
     <sink_key>1</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_float_to_complex_0</source_block_id>
+    <source_block_id>blocks_float_to_complex_0</source_block_id>
     <sink_block_id>chaos_dcsk_mod_cbc_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_vector_source_x_0</source_block_id>
-    <sink_block_id>blks2_packet_encoder_0</sink_block_id>
+    <source_block_id>blocks_packed_to_unpacked_xx_0</source_block_id>
+    <sink_block_id>chaos_dcsk_mod_cbc_0</sink_block_id>
     <source_key>0</source_key>
-    <sink_key>0</sink_key>
+    <sink_key>1</sink_key>
   </connection>
   <connection>
-    <source_block_id>chaos_dcsk_mod_cbc_0</source_block_id>
-    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_block_id>blocks_throttle_0</source_block_id>
+    <sink_block_id>channels_channel_model_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_throttle_0</source_block_id>
-    <sink_block_id>gr_channel_model_0</sink_block_id>
+    <source_block_id>blocks_vector_source_x_0</source_block_id>
+    <sink_block_id>blks2_packet_encoder_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_channel_model_0</source_block_id>
+    <source_block_id>channels_channel_model_0</source_block_id>
     <sink_block_id>chaos_dcsk_demod_cb_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>blks2_packet_encoder_0</source_block_id>
-    <sink_block_id>gr_packed_to_unpacked_xx_0</sink_block_id>
+    <source_block_id>channels_channel_model_0</source_block_id>
+    <sink_block_id>wxgui_fftsink2_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
-  <connection>
-    <source_block_id>gr_packed_to_unpacked_xx_0</source_block_id>
-    <sink_block_id>chaos_dcsk_mod_cbc_0</sink_block_id>
-    <source_key>0</source_key>
-    <sink_key>1</sink_key>
-  </connection>
   <connection>
     <source_block_id>chaos_dcsk_demod_cb_0</source_block_id>
     <sink_block_id>blks2_packet_decoder_0</sink_block_id>
@@ -640,14 +937,14 @@
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>blks2_packet_decoder_0</source_block_id>
-    <sink_block_id>gr_file_sink_0</sink_block_id>
+    <source_block_id>chaos_dcsk_mod_cbc_0</source_block_id>
+    <sink_block_id>blocks_throttle_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_channel_model_0</source_block_id>
-    <sink_block_id>wxgui_fftsink2_0</sink_block_id>
+    <source_block_id>chaos_gen_logi_map_f_0</source_block_id>
+    <sink_block_id>blocks_deinterleave_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
diff --git a/examples/grc/logmap_filter_demo.grc b/examples/grc/logmap_filter_demo.grc
index 8ded539..d92e225 100644
--- a/examples/grc/logmap_filter_demo.grc
+++ b/examples/grc/logmap_filter_demo.grc
@@ -1,62 +1,68 @@
-<?xml version='1.0' encoding='ASCII'?>
+<?xml version='1.0' encoding='utf-8'?>
+<?grc format='1' created='3.7.11'?>
 <flow_graph>
   <timestamp>Sat Nov 10 21:16:05 2012</timestamp>
   <block>
-    <key>variable</key>
+    <key>options</key>
     <param>
-      <key>id</key>
-      <value>samp_rate</value>
+      <key>author</key>
+      <value>Julien Olivain &lt;julien.olivain@lacime.etsmtl.ca&gt;</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>window_size</key>
+      <value>1280, 1024</value>
     </param>
     <param>
-      <key>value</key>
-      <value>100000</value>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>description</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(151, 11)</value>
+      <value>(8, 4)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>options</key>
     <param>
-      <key>id</key>
-      <value>logmap_filter_demo</value>
+      <key>generate_options</key>
+      <value>wx_gui</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>hier_block_src_path</key>
+      <value>.:</value>
     </param>
     <param>
-      <key>title</key>
-      <value>LogMap Filter Demo</value>
+      <key>id</key>
+      <value>logmap_filter_demo</value>
     </param>
     <param>
-      <key>author</key>
-      <value>Julien Olivain &lt;julien.olivain@lacime.etsmtl.ca&gt;</value>
+      <key>max_nouts</key>
+      <value>0</value>
     </param>
     <param>
-      <key>description</key>
+      <key>qt_qss_theme</key>
       <value></value>
     </param>
     <param>
-      <key>window_size</key>
-      <value>1280, 1024</value>
-    </param>
-    <param>
-      <key>generate_options</key>
-      <value>wx_gui</value>
+      <key>realtime_scheduling</key>
+      <value></value>
     </param>
     <param>
-      <key>category</key>
-      <value>Custom</value>
+      <key>run_command</key>
+      <value>{python} -u {filename}</value>
     </param>
     <param>
       <key>run_options</key>
@@ -67,70 +73,109 @@
       <value>True</value>
     </param>
     <param>
-      <key>max_nouts</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>realtime_scheduling</key>
+      <key>thread_safe_setters</key>
       <value></value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(10, 10)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>title</key>
+      <value>LogMap Filter Demo</value>
     </param>
   </block>
   <block>
-    <key>wxgui_histosink2</key>
+    <key>variable</key>
     <param>
-      <key>id</key>
-      <value>wxgui_histosink2_0</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>title</key>
-      <value>Histogram Plot</value>
+      <key>_coordinate</key>
+      <value>(176, 4)</value>
     </param>
     <param>
-      <key>num_bins</key>
-      <value>100</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
     <param>
-      <key>frame_size</key>
+      <key>id</key>
+      <value>samp_rate</value>
+    </param>
+    <param>
+      <key>value</key>
       <value>100000</value>
     </param>
+  </block>
+  <block>
+    <key>blocks_file_source</key>
     <param>
-      <key>win_size</key>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>grid_pos</key>
+      <key>comment</key>
       <value></value>
     </param>
     <param>
-      <key>notebook</key>
+      <key>affinity</key>
       <value></value>
     </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>file</key>
+      <value>/dev/urandom</value>
+    </param>
     <param>
       <key>_coordinate</key>
-      <value>(650, 128)</value>
+      <value>(24, 108)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>id</key>
+      <value>blocks_file_source_0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>int</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
   </block>
   <block>
-    <key>chaos_logmap_filter_ff</key>
+    <key>blocks_int_to_float</key>
     <param>
-      <key>id</key>
-      <value>chaos_logmap_filter_ff_0</value>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
       <key>_enabled</key>
@@ -138,127 +183,203 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(337, 142)</value>
+      <value>(200, 116)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_int_to_float</key>
     <param>
       <key>id</key>
-      <value>gr_int_to_float_0</value>
+      <value>blocks_int_to_float_0</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
       <key>scale</key>
       <value>2.**31</value>
     </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+  </block>
+  <block>
+    <key>blocks_throttle</key>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
     <param>
       <key>_coordinate</key>
-      <value>(182, 140)</value>
+      <value>(512, 116)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_throttle</key>
     <param>
       <key>id</key>
-      <value>gr_throttle_0</value>
+      <value>blocks_throttle_0</value>
     </param>
     <param>
-      <key>_enabled</key>
+      <key>ignoretag</key>
       <value>True</value>
     </param>
     <param>
-      <key>type</key>
-      <value>float</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
       <key>samples_per_second</key>
       <value>samp_rate</value>
     </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
     <param>
       <key>vlen</key>
       <value>1</value>
     </param>
+  </block>
+  <block>
+    <key>chaos_logmap_filter_ff</key>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>comment</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
     <param>
       <key>_coordinate</key>
-      <value>(487, 140)</value>
+      <value>(360, 120)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
-  </block>
-  <block>
-    <key>gr_file_source</key>
     <param>
       <key>id</key>
-      <value>gr_file_source_0</value>
+      <value>chaos_logmap_filter_ff_0</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>file</key>
-      <value>/dev/urandom</value>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_histosink2</key>
+    <param>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>type</key>
-      <value>int</value>
+      <key>comment</key>
+      <value></value>
     </param>
     <param>
-      <key>repeat</key>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>vlen</key>
-      <value>1</value>
+      <key>frame_size</key>
+      <value>100000</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(21, 134)</value>
+      <value>(696, 100)</value>
     </param>
     <param>
       <key>_rotation</key>
       <value>0</value>
     </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>id</key>
+      <value>wxgui_histosink2_0</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>num_bins</key>
+      <value>100</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Histogram Plot</value>
+    </param>
+    <param>
+      <key>win_size</key>
+      <value></value>
+    </param>
   </block>
   <connection>
-    <source_block_id>gr_throttle_0</source_block_id>
-    <sink_block_id>wxgui_histosink2_0</sink_block_id>
+    <source_block_id>blocks_file_source_0</source_block_id>
+    <sink_block_id>blocks_int_to_float_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_int_to_float_0</source_block_id>
+    <source_block_id>blocks_int_to_float_0</source_block_id>
     <sink_block_id>chaos_logmap_filter_ff_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>chaos_logmap_filter_ff_0</source_block_id>
-    <sink_block_id>gr_throttle_0</sink_block_id>
+    <source_block_id>blocks_throttle_0</source_block_id>
+    <sink_block_id>wxgui_histosink2_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gr_file_source_0</source_block_id>
-    <sink_block_id>gr_int_to_float_0</sink_block_id>
+    <source_block_id>chaos_logmap_filter_ff_0</source_block_id>
+    <sink_block_id>blocks_throttle_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>