Fixing RivaTTSService error handler.

src/pipecat/services/riva/tts.py

@@ -166,7 +166,6 @@ class RivaTTSService(TTSService):
                 add_response(None)
             except Exception as e:
                 logger.error(f"{self} exception: {e}")
-                yield ErrorFrame(error=f"{self} error: {e}")
                 add_response(None)
 
         await self.start_ttfb_metrics()
@@ -191,6 +190,7 @@ class RivaTTSService(TTSService):
                 resp = await asyncio.wait_for(queue.get(), timeout=RIVA_TTS_TIMEOUT_SECS)
         except asyncio.TimeoutError:
             logger.error(f"{self} timeout waiting for audio response")
+            yield ErrorFrame(error=f"{self} error: {e}")
 
         await self.start_tts_usage_metrics(text)
         yield TTSStoppedFrame()