Comet lake PCH-LPc AVS - no sound


Just installed latest version of manjaro mate. The problem I have is not unique to Manjaro Mate. I also installed fedora 34 mate and ubuntu mate with the same results.

Comet lake PCH-LP CAVS is the integrated sound chip on my laptop system, an acer spin 713 chromebook.

To be clear, on the spin 713, I disabled the google security chip, wiped out chromeos, installed a Coreboot UFEI bios from mrchromebox and have installed various linux distros without incident, except for this sound chip either not being detected or not functioning.

On Manjaro, the card is detected. Pulse audio, pavucontrol, shows an active meter on the analog output port if I play something. However no sound comes from the speakers.

In Mate, the chip set is detected on the volume control panel applet as Sound preferences:Hardware:

Comet Lake PCH-LP cAVS
1 output-2 inputs

Choices for the speaker-microphone tests are:

Stereo Output + Stereo input
Stereo Output
Stereo Input

The speaker test fails.

Sound-preferences:Output also shows the chip set, but the connector choice shows only one option; Analog Output.

alsamixer shows:

card pulseaudio
mixer pulseaudio


0 [sofrt562 ]: sof-rt562 - sof-rt562 Google-Kindred-rev7

To me all this means alsamixer does not see the chip, Mate sound does see the chip but sound output goes to Analog Output, to which nothing is connected.

Any suggestions as to how to fix this would be greatly appreciated.


Colby "

:+1: Welcome to Manjaro! :+1:

  1. Please read this:
    How to provide good information
    and press the three dots below your post and press the :pencil2: to give us more information so we can see what’s really going on.
    Now we know the symptom of the disease, but we need some more probing to know where the origin lies… :grin:
  2. An inxi --admin --verbosity=7 --filter --no-host --width would be the minimum required information for us to be able to help you. (Personally Identifiable Information like serial numbers and MAC addresses will be filtered out by the above command)
    Also, please copy-paste that output in-between 3 backticks ``` at the beginning and end of the code/text.
  3. the output of pacmd dump-volumes would be appreciated as well
  4. You posted this is the #support:graphic-cards subsection, so I reclassified this to #support:sound


P.S. If you want to notify me that you did provide this information, please :heart: this message and I’ll come back and have another look.

The command alsamixer without additional options is showing PulseAudio virtual level controls

To see ALSA controls for the onboard audio codec

alsamixer --card=0 --view=all

But a screenshot of this is no good for troubleshooting. If you need further help use this command to get text data

amixer -c0
1 Like