Fixed the audio/visual screwups

With the help of Toby, effects in the channels work and the peak
displays correctly. However the freeze-up bug is still wreaking havoc.

include/FxMixer.h

@@ -52,6 +52,7 @@ class FxChannel : public ThreadableJob
 		QString m_name;
 		QMutex m_lock;
 		int m_channelIndex; // what channel index are we
+		bool m_queued; // are we queued up for rendering yet?
 
 		// pointers to other channels that this one sends to
 		QVector<fx_ch_t> m_sends;

include/mixer.h

@@ -569,11 +569,16 @@ public:
 		}
 	}
 
-	template<typename T>
-	static void fillJobQueue( const T & _vec )
+	static void resetJobQueue()
 	{
 		s_jobQueue.queueSize = 0;
 		s_jobQueue.itemsDone = 0;
+	}
+
+	template<typename T>
+	static void fillJobQueue( const T & _vec )
+	{
+		resetJobQueue();
 		for( typename T::ConstIterator it = _vec.begin(); it != _vec.end(); ++it )
 		{
 			addJob( *it );