I am completely stuck with this and I no idea where to investigate further. So, these are the points I assembled so far:
$ inxi -Fazy
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Audio:
Device-1: Intel Sunrise Point-LP HD Audio vendor: Acer Incorporated ALI
driver: snd_hda_intel v: kernel alternate: snd_soc_skl bus ID: 00:1f.3
chip ID: 8086:9d70
Sound Server: ALSA v: k5.4.80-2-MANJARO
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- The problem is dependend on the user. There are four users on my laptop: on 2 of them, it works, on 1 it does not work, 1 untested. This one user for whom it fails does not have admin (or sudo or wheel) privileges.
- PulseAudio mixer and ALSA mixer interpret the problem the same way: There is a microphone, but it is muted and it cannot be unmuted.
- No application can access the microphone. Applications (like Zoom) don’t even list the microphone.
- The problem is independend from the microphone: The laptop’s internal microphone as well as a connected headset show up the same (present, but somehow disabled, and not available in applications).
- Until two days ago, it was working fine. There was no update in between.
So summarized: Chances are that the user made some strange settings I am not aware of. It does not look like a system-wide problem (otherwise, all users were affected).
Does anyone have an idea?