--- mediaproxy/mediacontrol.py.orig	2009-12-10 09:44:50.000000000 +0100
+++ mediaproxy/mediacontrol.py	2009-12-10 13:07:41.000000000 +0100
@@ -183,7 +183,8 @@
                 return
             self.substream.send_data(self, data)
             if self.timer:
-                self.timer.cancel()
+                if self.timer.active():
+                    self.timer.cancel()
                 self.timer = None
             if self.codec == "Unknown" and self.substream is self.substream.stream.rtp:
                 try: