Dear Maintainer,

It seems like Pulseaudio is unable to capture audio input from the microphone
in this laptop, an HP Elitebook 840 G9 without extra, somewhat hard to find,
configurations.


I was seeing the following:
 * in Cinnamon's Sound Settings UI (`cinnamon-settings sound`): one input
   device with its input level always at 0%.

 * in `pavucontrol`: two input devices (+ a "Monitor of..." one).
 ** One is called "Alder Lake PCH-P High Definition Audio Controller Stereo",
    and its input level is constantly oscillating at a low level.
    It does not react to any sound going on here.
 ** The other has the same name, except it doesn't mention "Stereo".
    Its input level is constantly empty.


I was able to get a working setup with the following:

1. I noticed that some programs (VLC and Audacity) are able to capture audio
   from a device identified as "hw:0,7", which seems to be related to Alsa.
   Others programs do not detect that device (such as Kazam, Zoom, and
   the system audio meters mentioned above).

2. After trying out many tips found online, I discovered one that suggested
   adding the following line to the /etc/pulse/default.pa file:
     load-module module-alsa-source device=hw:0,7

3. After a reboot, I can now select a working microphone.


Could it be possible to get a working microphone configuration in Debian for
Pulseaudio-bound programs without this manual discovery and configuration?

Extra:

 * The audio card is identified by the following in lspci:
00:1f.3 Multimedia audio controller: Intel Corporation Alder Lake PCH-P High
Definition Audio Controller (rev 01)
        Subsystem: Hewlett-Packard Company Alder Lake PCH-P High Definition
Audio Controller
        Flags: bus master, fast devsel, latency 64, IRQ 204, IOMMU group 14
        Memory at 603d1c8000 (64-bit, non-prefetchable) [size=16K]
        Memory at 603d000000 (64-bit, non-prefetchable) [size=1M]
        Capabilities: <access denied>
        Kernel driver in use: sof-audio-pci-intel-tgl
        Kernel modules: snd_hda_intel, snd_sof_pci_intel_tgl

 * I have the firmware-sof-signed package installed (without it
I don't get any sound output):

$ apt-cache policy firmware-sof-signed
firmware-sof-signed:
  Installed: 2.2.4-1
  Candidate: 2.2.4-1
  Version table:
 *** 2.2.4-1 500
        500 https://deb.debian.org/debian bookworm/non-free-firmware amd64
Packages
        100 /var/lib/dpkg/status


Feel free to ask for any additional information you may find relevant.


Thank you,
Luís Picciochi Oliveira