Keep jitter playback moving after local drops

gumble/gumbleopenal/stream.go

@@ -464,6 +464,12 @@ func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 			for {
 				pkt := popNext()
 				if pkt == nil {
+					// A locally dropped packet must not permanently stall the
+					// jitter buffer waiting for a sequence number that cannot arrive.
+					if len(jitterBuf) > 0 && jitterBuf[0].Sequence > jitterNextSeq {
+						jitterNextSeq = jitterBuf[0].Sequence
+						continue
+					}
 					break
 				}
 				reclaim()