Cannot use listed audio device

[mlowijs]

I'm trying to use the Sendspin daemon with one of the ALSA audio devices on my system.
The audio device I want to use is default:CARD=S4.
It is listed by sendspin audio-devices list:

[michiel@sqz-badkamer ~]$ sendspin audio-devices list
Available audio output devices:

  [0] Sound Blaster Play! 4: USB Audio (hw:0,0)
       Channels: 2, Sample rate: 44100.0 Hz
  [1] sysdefault
       Channels: 128, Sample rate: 48000.0 Hz
  [2] front
       Channels: 2, Sample rate: 44100.0 Hz
  [3] surround40
       Channels: 2, Sample rate: 44100.0 Hz
  [4] iec958
       Channels: 2, Sample rate: 44100.0 Hz
  [5] spdif
       Channels: 2, Sample rate: 44100.0 Hz
  [6] default (default)
       Channels: 128, Sample rate: 48000.0 Hz
  [7] dmix
       Channels: 2, Sample rate: 48000.0 Hz

To select an audio device:
  sendspin --audio-device 0
  sendspin daemon --audio-device 0

ALSA devices (use by name with --audio-device):

  null
       Discard all samples (playback) or generate zero samples (capture)
  default
       Default Audio Device
  sysdefault
       Default Audio Device
  default:CARD=S4
       Sound Blaster Play! 4, USB Audio
  sysdefault:CARD=S4
       Sound Blaster Play! 4, USB Audio
  front:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround21:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround40:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround41:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround50:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround51:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  surround71:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio
  iec958:CARD=S4,DEV=0
       Sound Blaster Play! 4, USB Audio

Recommended for desktop usage:

  default      System default

However, when I start sendspin, it seems the device is not seen:

[michiel@sqz-badkamer ~]$ sendspin daemon --audio-device 'default:CARD=S4' --name Badkamer
INFO:sendspin.audio_devices:Using audio device default:CARD=S4: default:CARD=S4
WARNING:sendspin.cli:No volume control available for device 'default:CARD=S4' (no ALSA mixer controls and PulseAudio/PipeWire not reachable), falling back to software volume control
INFO:sendspin.audio:C volume extension unavailable; falling back to numpy (slower)
INFO:sendspin.daemon.daemon:Starting Sendspin daemon: sendspin-cli-sqz-badkamer
INFO:sendspin.daemon.daemon:Listening for server connections on port 8928 (mDNS: _sendspin._tcp.local.)
INFO:aiosendspin.client.listener:ClientListener started on port 8928, path /sendspin
INFO:aiosendspin.client.listener:mDNS advertising client 'sendspin-cli-sqz-badkamer' on port 8928 with path /sendspin
INFO:sendspin.daemon.daemon:Server connected
ERROR:aiosendspin.client.listener:Unhandled exception in on_connection callback for 192.168.11.11
Traceback (most recent call last):
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/aiosendspin/client/listener.py", line 146, in _handle_websocket
    await self._on_connection(ws)
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sendspin/daemon/daemon.py", line 294, in _handle_server_connection
    client = self._create_client()
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sendspin/daemon/daemon.py", line 92, in _create_client
    supported_formats = detect_supported_audio_formats(self._args.audio_device)
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sendspin/audio_devices.py", line 121, in detect_supported_audio_formats
    supported_rates = [r for r in sample_rates if _check_format(device, r, 2, "int16")]
                                                  ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sendspin/audio_devices.py", line 86, in _check_format
    sounddevice.check_output_settings(
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        device=device.device_id,
        ^^^^^^^^^^^^^^^^^^^^^^^^
    ...<2 lines>...
        dtype=dtype,
        ^^^^^^^^^^^^
    )
    ^
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sounddevice.py", line 704, in check_output_settings
    parameters, dtype, samplesize, samplerate = _get_stream_parameters(
                                                ~~~~~~~~~~~~~~~~~~~~~~^
        'output', device=device, channels=channels, dtype=dtype, latency=None,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        extra_settings=extra_settings, samplerate=samplerate)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sounddevice.py", line 2734, in _get_stream_parameters
    device = _get_device_id(device, kind, raise_on_error=True)
  File "/usr/local/share/uv/tools/sendspin/lib/python3.14/site-packages/sounddevice.py", line 2900, in _get_device_id
    raise ValueError(
        'No ' + kind + ' device matching ' + repr(id_or_query_string))
ValueError: No output device matching 'default:CARD=S4'

Output from amixer:

[michiel@sqz-badkamer ~]$ amixer
Simple mixer control 'PCM',0
  Capabilities: pvolume pswitch pswitch-joined
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 175
  Mono:
  Front Left: Playback 175 [100%] [0.00dB] [on]
  Front Right: Playback 175 [100%] [0.00dB] [on]
Simple mixer control 'Mic',0
  Capabilities: cvolume cswitch cswitch-joined
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 74
  Front Left: Capture 74 [100%] [10.00dB] [on]
  Front Right: Capture 74 [100%] [10.00dB] [on]

[michiel@sqz-badkamer ~]$ sendspin --version
sendspin 7.3.0