Fix decoder change issue in audio_stream_change_decoder

src/audiostream.c

@@ -259,17 +259,16 @@ void audio_stream_change_decoder(AudioStream *stream, int payload){
 	if (pt!=NULL){
 		MSFilter *dec=ms_filter_create_decoder(pt->mime_type);
 		if (dec!=NULL){
+			MSFilter *nextFilter = stream->decoder->outputs[0]->next;
 			ms_filter_unlink(stream->rtprecv, 0, stream->decoder, 0);
-			if (stream->dtmfgen)
-				ms_filter_unlink(stream->decoder, 0, stream->dtmfgen, 0);
+			ms_filter_unlink(stream->decoder, 0, nextFilter, 0);
 			ms_filter_postprocess(stream->decoder);
 			ms_filter_destroy(stream->decoder);
 			stream->decoder=dec;
 			if (pt->recv_fmtp!=NULL)
 				ms_filter_call_method(stream->decoder,MS_FILTER_ADD_FMTP,(void*)pt->recv_fmtp);
 			ms_filter_link(stream->rtprecv, 0, stream->decoder, 0);
-			if (stream->dtmfgen)
-				ms_filter_link(stream->decoder, 0, stream->dtmfgen, 0);
+			ms_filter_link(stream->decoder, 0, nextFilter, 0);
 			ms_filter_preprocess(stream->decoder,stream->ticker);
 
 		}else{