HP ZBook Fury 16 G10 (103c:8b92, Raptor Lake-S): internal DMIC captures only digital silence (IPC3 and IPC4) #6004

Title:

alsa-info.txt

dmesg.txt

nhlt.zip

Hardware / software

• Laptop: HP ZBook Fury 16 G10 Mobile Workstation PC, SKU 7B630AV, board 8B92
• BIOS: V96 Ver. 01.11.01 (2025-12-16); integrated microphone enabled in BIOS
• Audio: Intel Raptor Lake HDA [8086:7a50], subsystem 103c:8b92; Realtek ALC245 + 2x Cirrus CS35L41 (SPI, CSC3551)
• OS: Ubuntu 26.04.1 LTS, kernel 7.0.0-42-generic
• firmware-sof-signed 2025.12.2-1, linux-firmware 20260319, alsa-ucm-conf 1.2.15.3-1ubuntu1.7, PipeWire 1.6.2, WirePlumber 0.5.13

Problem

The internal digital microphones record only digital silence: every sample has the same constant value, with no noise floor. Speakers, HDMI and the headset jack enumerate normally. The microphone works in Windows on the same machine, so the hardware is fine.

Default configuration (IPC3)

• sof-rpl-s.ri FW 2:2:0-57864, topology intel/sof-tplg/sof-hda-generic-4ch.tplg
• DMICs detected in NHLT tables: 4, machine driver skl_hda_dsp_generic
• The stream opens with no kernel errors. After a short burst during the first ~0.5 s, all 4 channels are constant.
• The result is the same with PipeWire stopped, using arecord -D hw:1,6 -c 4 -r 48000 -f S16_LE and hw:1,7 (16 kHz). All channels: one distinct sample value.
• Mixer: Dmic0 Capture Switch on,on,on,on; Dmic0 Capture Volume 70/70; Dmic1 2nd Capture Volume 50. The GNOME microphone privacy switch is off, and the micmute LED is 0.

Things tried

All options have since been reverted to the defaults.

Possibly relevant

snd_hda_codec_alc269 ehdaudio0D0: ALC245: picked fixup  for PCI SSID 103c:8b92

The fixup name is empty: there is no patch_realtek quirk entry for 103c:8b92. Other ZBook G10 variants have CS35L41 and GPIO/LED quirks. On some HP designs, DMIC power or mute is gated through a codec GPIO, which could explain digital-zero capture.

Also: hp-wmi: query 0x4 returned error 0x5 / Failed to apply initial fan settings: -22

Attachments

• alsa-info.txt (sudo alsa-info --no-upload --output alsa-info.txt)
• nhlt.dat (sudo cat /sys/firmware/acpi/tables/NHLT > nhlt.dat)
• dmesg.txt (sudo dmesg > dmesg.txt)