diff --git a/pifacecommon/spi.py b/pifacecommon/spi.py
index 2aa5cfb..40b5d6f 100644
--- a/pifacecommon/spi.py
+++ b/pifacecommon/spi.py
@@ -65,7 +65,8 @@ def spisend(self, bytes_to_send):
         transfer = spi_ioc_transfer(
             tx_buf=ctypes.addressof(wbuffer),
             rx_buf=ctypes.addressof(rbuffer),
-            len=ctypes.sizeof(wbuffer)
+            len=ctypes.sizeof(wbuffer),
+	    speed_hz=ctypes.c_uint32(100000)
         )
 
         if self.spi_callback is not None:
diff --git a/pifacecommon/version.py b/pifacecommon/version.py
index ea5d65f..0d6a4f2 100644
--- a/pifacecommon/version.py
+++ b/pifacecommon/version.py
@@ -1 +1 @@
-__version__ = '4.2.0'
+__version__ = '4.2.1'