PortAudioError: Unanticipated host error [PaErrorCode -9999]: 'No space left on device' [ALSA error -28] #624
Description
Platform/OS: Raspberry Pi 4B, Linux raspberrypi4b 6.12.62+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.12.62-1+rpt1 (2025-12-18) aarch64 GNU/Linux
Python 3.13.5
I am using sounddevice Version: 0.5.5 with PortAudio version ('PortAudio V19.6.0-devel, revision 396fe4b6699ae929d3a685b3ef8a7e97396139a4') to play a wav file to a USB Audio device.
When I try to play audio via sd.play function I get the following error:
PortAudioError: Error opening OutputStream: Unanticipated host error [PaErrorCode -9999]: 'No space left on device' [ALSA error -28]
(venv) rpi4b@raspberrypi4b:~/tmp_auracast $ ipython
Python 3.13.5 (main, Jun 25 2025, 18:55:22) [GCC 14.2.0]
Type 'copyright', 'credits' or 'license' for more information
IPython 9.10.0 -- An enhanced Interactive Python. Type '?' for help.
Tip: You can use `files = !ls *.png`
In [1]: import soundfile
In [2]: import sounddevice as sd
In [3]: sd.query_devices()
Out[3]:
0 bcm2835 Headphones: - (hw:0,0), ALSA (0 in, 8 out)
> 1 UT02C Aura: USB Audio (hw:3,0), ALSA (1 in, 2 out)
2 UT02C Aura: USB Audio (hw:4,0), ALSA (1 in, 2 out)
3 UT02C Aura: USB Audio (hw:5,0), ALSA (1 in, 2 out)
4 UT02C Aura: USB Audio (hw:6,0), ALSA (1 in, 2 out)
5 sysdefault, ALSA (0 in, 128 out)
< 6 default, ALSA (0 in, 128 out)
7 dmix, ALSA (0 in, 2 out)
In [4]: data, _ = soundfile.read("../Downloads/1000-Hz-Tone.wav")
In [5]: sd.play(data, device=1)
Expression 'r' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 2097
Expression 'PaAlsaStreamComponent_FinishConfigure( &self->playback, hwParamsPlayback, outParams, self->primeBuffers, realSr, outputLatency )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 2737
Expression 'PaAlsaStream_Configure( stream, inputParameters, outputParameters, sampleRate, framesPerBuffer, &inputLatency, &outputLatency, &hostBufferSizeMode )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', l
ine: 2842
---------------------------------------------------------------------------
PortAudioError Traceback (most recent call last)
Cell In[5], line 1
----> 1 sd.play(data, device=1)
File ~/tmp_auracast/venv/lib/python3.13/site-packages/sounddevice.py:183, in play(data, samplerate, mapping, blocking, loop, **kwargs)
180 ctx.write_outdata(outdata)
181 ctx.callback_exit()
--> 183 ctx.start_stream(OutputStream, samplerate, ctx.output_channels,
184 ctx.output_dtype, callback, blocking,
185 prime_output_buffers_using_stream_callback=False,
186 **kwargs)
File ~/tmp_auracast/venv/lib/python3.13/site-packages/sounddevice.py:2664, in _CallbackContext.start_stream(self, StreamClass, samplerate, channels, dtype, callback, blocking, **kwargs)
2661 def start_stream(self, StreamClass, samplerate, channels, dtype, callback,
2662 blocking, **kwargs):
2663 stop() # Stop previous playback/recording
-> 2664 self.stream = StreamClass(samplerate=samplerate,
2665 channels=channels,
2666 dtype=dtype,
2667 callback=callback,
2668 finished_callback=self.finished_callback,
2670 self.stream.start()
2671 global _last_callback
File ~/tmp_auracast/venv/lib/python3.13/site-packages/sounddevice.py:1532, in OutputStream.__init__(self, samplerate, blocksize, device, channels, dtype, latency, extra_settings, callback, finished_callback, c
lip_off, dither_off, never_drop_input, prime_output_buffers_using_stream_callback)
1500 def __init__(self, samplerate=None, blocksize=None,
1501 device=None, channels=None, dtype=None, latency=None,
1502 extra_settings=None, callback=None, finished_callback=None,
1503 clip_off=None, dither_off=None, never_drop_input=None,
1504 prime_output_buffers_using_stream_callback=None):
1505 """PortAudio output stream (using NumPy).
1506
1507 This has the same methods and attributes as `Stream`, except
(...) 1530
1531 """
-> 1532 _StreamBase.__init__(self, kind='output', wrap_callback='array',
1533 **_remove_self(locals()))
File ~/tmp_auracast/venv/lib/python3.13/site-packages/sounddevice.py:914, in _StreamBase.__init__(self, kind, samplerate, blocksize, device, channels, dtype, latency, extra_settings, callback, finished_callbac
k, clip_off, dither_off, never_drop_input, prime_output_buffers_using_stream_callback, userdata, wrap_callback)
912 userdata = _ffi.NULL
913 self._ptr = _ffi.new('PaStream**')
--> 914 _check(_lib.Pa_OpenStream(self._ptr, iparameters, oparameters,
915 samplerate, blocksize, stream_flags,
916 callback_ptr, userdata),
917 f'Error opening {self.__class__.__name__}')
919 # dereference PaStream** --> PaStream*
920 self._ptr = self._ptr[0]
File ~/tmp_auracast/venv/lib/python3.13/site-packages/sounddevice.py:2836, in _check(err, msg)
2834 hosterror_text = _ffi_string(info.errorText).decode()
2835 hosterror_info = host_api, info.errorCode, hosterror_text
-> 2836 raise PortAudioError(errormsg, err, hosterror_info)
2838 raise PortAudioError(errormsg, err)
PortAudioError: Error opening OutputStream: Unanticipated host error [PaErrorCode -9999]: 'No space left on device' [ALSA error -28]
I get a similar problem when calling sd.check_output_settings(device=1)
I checked which applications are using the audio devices and looks like pipewire, wirepluber audio services are involved but this should not be a problem I guess ?
(venv) rpi4b@raspberrypi4b:~/tmp_auracast $ fuser -v /dev/snd/*
USER PID ACCESS COMMAND
/dev/snd/controlC0: rpi4b 1220 F.... wireplumber
/dev/snd/controlC3: rpi4b 1220 F.... wireplumber
/dev/snd/seq: rpi4b 1217 F.... pipewire