Headphone mic input is very quiet and low quality

[Constancies]

Your system information

I'm running SteamOS on my Steam Deck OLED 512GB.

• Steam client version: 1726683985
• SteamOS version: 3.5.19
• Opted into Steam client beta?: No
• Opted into SteamOS beta?: No
• Have you checked for updates in Settings > System?: Yes

Please describe your issue in as much detail as possible:

I've noticed that the microphone input from headphones tends to be very quiet and somewhat low quality, almost as if a noise gate is being applied by the system and the gain is being extremely reduced. For instance, whenever I try doing a recording in OBS or GNOME Sound Recorder from Flathub, in both instances the microphone input is almost inaudible.

I have been able to capture much cleaner sound through my Focusrite audio interface, though only after running the input through pure ALSA instead of through Pipewire, though I think that's likely due to a sample rate in pipewire issue unrelated to this one.

I would like to clarify that I have tested these headphones on other devices, such as my laptop running Linux (Tumbleweed), and the issue is not present there.

Steps for reproducing this issue:

1. In Desktop Mode, install GNOME Sound Recorder or OBS from Flathub (either works).
2. Make sure your input is set to the headphones' microphone.
3. Record a sound and listen to it through any speaker output.