Error opening RawStream: Device unavailable [PaErrorCode -9985]

[rkuchkarov]

When I run assistant_sample.py everything works fine. But when I run hotword_sample.py and say a hot word, the program crashes:

python3 hotword_sample.py
INFO:snowboy:Keyword 1 detected at time: 2020-06-14 19:22:37
Expression 'ret' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1736
Expression 'AlsaOpen( &alsaApi->baseHostApiRep, params, streamDir, &self->pcm )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1904
Expression 'PaAlsaStreamComponent_Initialize( &self->capture, alsaApi, inParams, StreamDirection_In, NULL != callback )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 2171
Expression 'PaAlsaStream_Initialize( stream, alsaHostApi, inputParameters, outputParameters, sampleRate, framesPerBuffer, callback, streamFlags, userData )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 2840
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "/home/pi/assistant-sample/assistant/hotword.py", line 68, in run
    self.detector.start(detected_callback=self.hotword_detected())
  File "/home/pi/assistant-sample/snowboydecoder.py", line 221, in start
    callback()
  File "/home/pi/assistant-sample/assistant/hotword.py", line 62, in callback
    self.assistant.start_conversation()
  File "/home/pi/assistant-sample/assistant/__init__.py", line 200, in start_conversation
    self._init_assistant()
  File "/home/pi/assistant-sample/assistant/__init__.py", line 107, in _init_assistant
    flush_size=self.audio_flush_size
  File "/home/pi/.local/lib/python3.7/site-packages/googlesamples/assistant/grpc/audio_helpers.py", line 190, in __init__
    blocksize=int(block_size/2),  # blocksize is in number of frames.
  File "/home/pi/.local/lib/python3.7/site-packages/sounddevice.py", line 1345, in __init__
    **_remove_self(locals()))
  File "/home/pi/.local/lib/python3.7/site-packages/sounddevice.py", line 861, in __init__
    'Error opening {0}'.format(self.__class__.__name__))
  File "/home/pi/.local/lib/python3.7/site-packages/sounddevice.py", line 2653, in _check
    raise PortAudioError(errormsg, err)
sounddevice.PortAudioError: Error opening RawStream: Device unavailable [PaErrorCode -9985]