[BUG] Internal microphone captures only constant tone/noise on Google Fleex Chromebook (sof-glkda7219max)

[Rainoutt]

Describe the bug
The internal microphone is detected correctly, but it never captures any voice audio.

Every recording contains only:

• a short high-pitched tone at the beginning
• constant digital noise/crackling afterwards

The speakers and headphone output work correctly, even the external mic works.

I tested both PipeWire and raw ALSA, so this does not appear to be a PipeWire issue, or even alsa.

I also extracted all four recorded channels individually and none of them contains my voice.

To Reproduce
install archlinux with all the correct firmware, pipewire and wireplumber, alsa-ucm-conf alsa-topology-conf and sof-firmware are correctly installed

Reproduction Rate
10/10

Expected behavior
to hear my voice in a recording

Impact
its annoying, but manageable

Environment

1. Branch name and commit hash of the 2 repositories: sof (firmware/topology) and linux (kernel driver).

   • Kernel: {Linux Chromebook 7.1.5-arch1-2 }
   • SOF: {sof-firmware 2025.12.2-1}

2. Name of the topology file
   [root@Chromebook julian]# cat /sys/kernel/debug/sof/fw_profile/tplg_name
   cat /sys/kernel/debug/sof/fw_profile/tplg_path
   sof-glk-da7219.tplg
   intel/sof-tplg

3. Name of the platform(s) on which the bug is observed.

   • Platform: {Dell 3100 chromebook with latest mrchromebook firmware, codename FLEEX, running Archlinux
     CPU: Gemini Lake Intel N4020}

Screenshots or console output
julian@Chromebook ~> sudo dmesg | grep -i "sof"
[sudo] contraseña para julian:
[ 0.026748] software IO TLB: area num 2.
[ 0.448179] PCI-DMA: Using software bounce buffering for IO (SWIOTLB)
[ 0.448181] software IO TLB: mapped [mem 0x00000000759d6000-0x00000000799d6000] (64MB)
[ 0.468099] xor: measuring software checksum speed
[ 0.672477] integrity: Loaded X.509 cert 'Microsoft Corporation UEFI CA 2011: 13adbf4309bd82709c8cd54f316ed522988a1bd4'
[ 0.672497] integrity: Loaded X.509 cert 'Microsoft UEFI CA 2023: 81aa6b3244c935bce0d6628af39827421e32497d'
[ 0.672516] integrity: Loaded X.509 cert 'Microsoft Windows Production PCA 2011: a92902398e16c49778cd90f99e4f9ae17c55af53'
[ 0.672535] integrity: Loaded X.509 cert 'Microsoft Corporation: Windows UEFI CA 2023: aefc5fbbbe055d8f8daa585473499417ab5a5272'
[ 7.487897] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti giometti@linux.it
[ 10.155122] sof-audio-pci-intel-apl 0000:00:0e.0: DSP detected with PCI class/subclass/prog-if 0x040100
[ 10.155260] sof-audio-pci-intel-apl 0000:00:0e.0: bound 0000:00:02.0 (ops intel_audio_component_bind_ops [i915])
[ 10.163239] sof-audio-pci-intel-apl 0000:00:0e.0: use msi interrupt mode
[ 10.221680] sof-audio-pci-intel-apl 0000:00:0e.0: hda codecs found, mask 4
[ 10.221691] sof-audio-pci-intel-apl 0000:00:0e.0: BT link detected in NHLT tables: 0x0
[ 10.221696] sof-audio-pci-intel-apl 0000:00:0e.0: DMICs detected in NHLT tables: 2
[ 10.221698] sof-audio-pci-intel-apl 0000:00:0e.0: NHLT device I2S(4) detected, ssp_mask 0x6
[ 10.230047] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware paths/files for ipc type 0:
[ 10.230058] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware file: intel/sof/community/sof-glk.ri
[ 10.230061] sof-audio-pci-intel-apl 0000:00:0e.0: Topology file: intel/sof-tplg/sof-glk-da7219.tplg
[ 10.231213] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware info: version 2:2:0-57864
[ 10.231219] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware: ABI 3:22:1 Kernel ABI 3:23:1
[ 10.282999] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware info: version 2:2:0-57864
[ 10.283010] sof-audio-pci-intel-apl 0000:00:0e.0: Firmware: ABI 3:22:1 Kernel ABI 3:23:1
[ 10.336162] sof-audio-pci-intel-apl 0000:00:0e.0: loading topology: intel/sof-tplg/sof-glk-da7219.tplg
[ 10.336282] sof-audio-pci-intel-apl 0000:00:0e.0: Topology: ABI 3:22:1 Kernel ABI 3:23:1
[ 10.336573] sof_da7219 glk_da7219_def: ASoC: Parent card not yet available, widget card binding deferred
[ 10.394973] sof_da7219 glk_da7219_def: ASoC: sink widget DMic overwritten
[ 10.395296] sof_da7219 glk_da7219_def: ASoC: driver name too long 'sof-glkda7219max' -> 'sof-glkda7219ma'
[ 10.499525] input: sof-glkda7219max Headset Jack as /devices/pci0000:00/0000:00:0e.0/glk_da7219_def/sound/card0/input10
[ 10.499621] input: sof-glkda7219max HDMI/DP,pcm=5 as /devices/pci0000:00/0000:00:0e.0/glk_da7219_def/sound/card0/input11
[ 10.500682] input: sof-glkda7219max HDMI/DP,pcm=6 as /devices/pci0000:00/0000:00:0e.0/glk_da7219_def/sound/card0/input12
[ 10.500742] input: sof-glkda7219max HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:0e.0/glk_da7219_def/sound/card0/input13
julian@Chromebook ~>

alsa-info.txt

julian@Chromebook ~> arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: sofglkda7219max [sof-glkda7219max], device 1: Headset () []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: sofglkda7219max [sof-glkda7219max], device 99: DMIC () []
Subdevices: 1/1
Subdevice #0: subdevice #0

Record (online-voice-recorder.com).mp3