diff --git a/examples/11_sound/01-fft.pd b/examples/11-sound/01-fft.pd
similarity index 100%
rename from examples/11_sound/01-fft.pd
rename to examples/11-sound/01-fft.pd
diff --git a/examples/11_sound/01-fft.py b/examples/11-sound/01-fft.py
similarity index 100%
rename from examples/11_sound/01-fft.py
rename to examples/11-sound/01-fft.py
diff --git a/examples/11_sound/02-in-out.pd b/examples/11-sound/02-in-out.pd
similarity index 100%
rename from examples/11_sound/02-in-out.pd
rename to examples/11-sound/02-in-out.pd
diff --git a/examples/11_sound/02-in-out.py b/examples/11-sound/02-in-out.py
similarity index 100%
rename from examples/11_sound/02-in-out.py
rename to examples/11-sound/02-in-out.py
diff --git a/examples/11_sound/03-sequencer.pd b/examples/11-sound/03-sequencer.pd
similarity index 100%
rename from examples/11_sound/03-sequencer.pd
rename to examples/11-sound/03-sequencer.pd
diff --git a/examples/11_sound/03-sequencer.py b/examples/11-sound/03-sequencer.py
similarity index 100%
rename from examples/11_sound/03-sequencer.py
rename to examples/11-sound/03-sequencer.py
diff --git a/examples/11_sound/04-audiosnails.pd b/examples/11-sound/04-audiosnails.pd
similarity index 100%
rename from examples/11_sound/04-audiosnails.pd
rename to examples/11-sound/04-audiosnails.pd
diff --git a/examples/11_sound/04-audiosnails.py b/examples/11-sound/04-audiosnails.py
similarity index 100%
rename from examples/11_sound/04-audiosnails.py
rename to examples/11-sound/04-audiosnails.py
diff --git a/nodebox/ext/noise.c b/nodebox/ext/noise.c
index 4f8a714..e5a4423 100644
--- a/nodebox/ext/noise.c
+++ b/nodebox/ext/noise.c
@@ -2,6 +2,8 @@
 // Based on: Malcolm Kesson, http://www.fundza.com/c4serious/noise/perlin/perlin.html
 // © 2002-4 Malcolm Kesson. All rights reserved.
 
+#include <Python.h>
+
 #include <math.h>
 #include <stdio.h>
 
@@ -48,8 +50,6 @@ double _generate(double x, double y, double z) {
 
 // -------------------------------------------------------------------------------------
 
-#include <Python.h> 
-
 static PyObject *
 generate(PyObject *self, PyObject *args) {
     double x, y, z, d;   
@@ -84,4 +84,5 @@ int main(int argc, char *argv[]) {
     Py_Initialize();
     initnoise();
     return 0;
-}
\ No newline at end of file
+}
+
diff --git a/nodebox/sound/process.py b/nodebox/sound/process.py
index 98f7b0f..a67d441 100644
--- a/nodebox/sound/process.py
+++ b/nodebox/sound/process.py
@@ -228,6 +228,8 @@ def start(self):
         if self.patch is None \
         or not os.path.exists(self.patch):
             raise PDError, "no PD patch file at '%s'" % self.patch
+        if not self._path:
+            raise PDError, "no PD application found"
         if not os.path.exists(self._path):
             raise PDError, "no PD application at '%s'" % self._path
         if not self._process:
@@ -286,4 +288,4 @@ def data(self):
     def stop(self):
         self._socket.connections -= 1
         self._socket.close()
-        self._socket = None
\ No newline at end of file
+        self._socket = None