Missing UCM profile for Realtek ALC4082 USB Audio (26ce:0a08) causing whole-card dropout
GitHub issues - opened <[email protected]>
| Newsgroups | org.alsa-project.alsa-devel |
|---|---|
| Message-ID | <[email protected]> |
alsa-project/alsa-ucm-conf issue #829 was opened from TIBILL: **Device:** Realtek ALC4082 USB Audio codec, USB ID 26ce:0a08 **Motherboard:** ASRock X870 Steel Legend WiFi **Distro:** CachyOS (Arch-based), kernel 7.0.x **alsa-ucm-conf version:** 1.2.16-2 **PipeWire:** 1.6.6, WirePlumber 0.5.14 **Problem:** No UCM profile exists for 26ce:0a08. The device falls back to a generic multi-device profile exposing 4 separate PCM playback devices (SPDIF, Speaker 8ch, Headphones, Mic), shown as split sinks (HiFi_7_1__SPDIF__sink, HiFi_7_1__Speaker__sink, HiFi_7_1__Headphones__sink) instead of one clean card profile. Only one PCM (device 3, S/PDIF output) is actually used. The mixer confirms only one PCM Playback Switch is enabled: PCM Playback Switch : off PCM Playback Switch,index=1 : off PCM Playback Switch,index=2 : on <- the one in use (S/PDIF) **Symptom:** Under normal use (browser video, especially transitioning between videos/episodes on streaming sites), the card intermittently gets abandoned by PipeWire and falls back to auto_null. Confirmed NOT a hardware/USB disconnect — dmesg shows no disconnect event for this device during the freeze. Logs at the freeze moment show: [ERROR:chromium/media/audio/pulse/pulse_util.cc:384] pa_operation is nullptr. [ERROR:chromium/services/audio/output_device_mixer_impl.cc:173] MixableOutputStream: Error during independent playback followed by KDE components reporting `No object for name "auto_null"`. Only fix is a full PipeWire/WirePlumber restart (`systemctl --user restart pipewire pipewire-pulse wireplumber`), which recovers it every time. Attempting `api.alsa.use-ucm = false` (disabling UCM entirely) results in complete loss of S/PDIF output — so the device requires SOME UCM profile to function at all, but the current generic fallback appears unstable, likely because PipeWire abandons the whole card when one of the 3 unused PCM endpoints fails to prepare (possibly related to PipeWire issue #4938). **Request:** a proper UCM profile for 26ce:0a08 that only exposes the working PCM device (device 3 / S/PDIF), so the unused Speaker/Headphones/Mic endpoints aren't probed and can't take the whole card down. **alsa-info.sh output:** [https://termbin.com/cpdns] Issue URL : https://github.com/alsa-project/alsa-ucm-conf/issues/829 Repository URL: https://github.com/alsa-project/alsa-ucm-conf