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Hardware • Re: No sound (dummy output)

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I hit this exact same issue on a ThinkPad T490 (Cannon Point-LP, ALC257) running Forky with kernel 6.18.5. Same symptoms — only HDMI profiles, no analog output, Dummy Output. I traced the root cause and it's a driver/UCM mismatch that's likely to bite anyone with Intel 8th-gen or newer audio on Debian testing/unstable.

Why it happens

Your pactl list confirms it — your Raptor Lake-P/U/H cAVS card is bound to the legacy snd_hda_intel driver:

Code:

alsa.driver_name = "snd_hda_intel"

The snd_intel_dspcfg module parameter dsp_driver defaults to 0 (auto), and on current kernels the auto-detection is picking the legacy HDA driver for these controllers instead of SOF (Sound Open Firmware). This gives the card the ALSA name HDA-Intel.

The problem is that the HDA-Intel UCM config (from alsa-ucm-conf) no longer supports plain Intel HDA cards. It was refactored to only handle AMD ACP configurations. You can verify this:

Code:

$ alsaucm -c HDA-Intel list _verbsALSA lib parser.c:305:(error_node) [error.ucm] UCM is not supported for this HDA model (HDA Intel PCH at ...)

Without UCM, PipeWire's ACP module can't build the analog output ports/profiles. It finds the HDMI outputs fine but the speaker and headphone output are simply absent — which is exactly what your pactl list Ports section shows (only hdmi-output-0 through hdmi-output-3, zero analog ports). No analog output ports means no analog output profile, so PipeWire falls back to the null sink: Dummy Output.

The pipewire-jack install likely fixed things for you coincidentally — possibly by triggering a module reload or ALSA device rescan on reboot. It's not a stable fix and as you suspected, it may break again.

The proper fix

Force the SOF driver. For Raptor Lake the SOF firmware is already installed via firmware-sof-signed, and the sof-hda-dsp UCM config properly defines analog output (speaker, headphones) as well as HDMI:

Code:

sudo tee /etc/modprobe.d/sof-audio.conf <<< 'options snd_intel_dspcfg dsp_driver=3'sudo reboot

After reboot your card should appear as sof-hda-dsp instead of HDA-Intel, and the full set of analog output profiles will be available. You can verify with:

Code:

cat /proc/asound/cards

It should show sof-hda-dsp rather than HDA-Intel.

To revert if needed:

Code:

sudo rm /etc/modprobe.d/sof-audio.confsudo reboot

Scope

This likely affects any Intel 8th-gen (Cannon Lake / Whiskey Lake) and newer HDA controller where dsp_driver=0 auto-selects the legacy driver instead of SOF. The working UCM config (sof-hda-dsp) only gets used when the SOF driver is active. This is arguably a bug in either alsa-ucm-conf (for dropping Intel HDA support from the HDA-Intel UCM path) or in snd_intel_dspcfg (for not preferring SOF on these controllers where it's the only path with working UCM).

Diagnostic quick-reference

Code:

# Check current driverwpctl inspect <device-id> | grep alsa.driver_name# Verify UCM fails on HDA-Intelalsaucm -c HDA-Intel list _verbs# Check DSP driver mode (0=auto, 1=legacy, 2=generic, 3=SOF)cat /sys/module/snd_intel_dspcfg/parameters/dsp_driver# Test hardware directly bypassing PipeWirespeaker-test -D hw:0,0 -c 2 -t wav -l 1

Statistics: Posted by fastly — 2026-02-09 22:45



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