diff --git a/rtcllm/a2a.py b/rtcllm/a2a.py
index edd9616..fcfebce 100644
--- a/rtcllm/a2a.py
+++ b/rtcllm/a2a.py
@@ -12,11 +12,16 @@ class LLMAudioStreamTrack(AudioStreamTrack):
 	
 	async def recv(self):
 		print(f'LLMAudioStreamTrack():recv() called ....')
-		b = self.get_audio_bytes()
-		if b is None:
-			return b
-		frame = AudioFrame.from_ndarray(io.BytesIO(b), format='s16', layout='mono')
-		return frame
+		try:
+			b = self.get_audio_bytes()
+			if b is None:
+				return b
+			frame = AudioFrame.from_ndarray(io.BytesIO(b), format='s16', layout='mono')
+			return frame
+		except Exception as e:
+			print_exc()
+			print(f'{self.__class__.__name__} recv() exception happened')
+			raise e
 
 	def set_cur_audio_iter(self):
 		if len(self.audio_iters) == 0:
diff --git a/rtcllm/aav.py b/rtcllm/aav.py
index 6942a60..38f8b3b 100644
--- a/rtcllm/aav.py
+++ b/rtcllm/aav.py
@@ -57,6 +57,7 @@ class MyAudioStreamTrack(AudioStreamTrack):
 
 	async def _recv(self):
 		if self.source is None:
+			print('self._recv() return None')
 			return None
 		f = await self.track.recv()
 		return f
diff --git a/rtcllm/rtc.py b/rtcllm/rtc.py
index 095673d..4e1035a 100644
--- a/rtcllm/rtc.py
+++ b/rtcllm/rtc.py
@@ -126,7 +126,8 @@ class RTCLLM:
 			'player':player,
 			'pc':pc
 		})
-		pc.addTrack(MyAudioStreamTrack(player))
+		pc.addTrack(llmtrack)
+		# pc.addTrack(MyAudioStreamTrack(player))
 		pc.addTrack(MyVideoStreamTrack(player))
 		# pc.addTrack(LoopingVideoTrack('./1.mp4'))
 		# pc.addTrack(player.video)