Arch Linux

mattboy9921

Member

Registered: 2020-11-05

Posts: 1

KDE Audio Levels Reset When Plugging/Unplugging USB Mic

I have Arch with KDE installed on a desktop. I use a USB audio interface for my microphone, which has its level set to 39%, otherwise it sounds like trash. I also have a USB webcam (Logitech C920) which has a mic as well and shows in the same list in System Settings > Hardware > Audio.

I frequently plug/unplug the webcam but every time I do so, it instantly resets the 39% value for my USB mic to 100%. Curiously, it only seems to apply to that one USB mic. Every other device stays at the value I set it to. How can I troubleshoot this, is there a log I can look at that might explain what's happening? How can I fix this so when I plug/unplug a USB audio source, it doesn't reset my USB mic's level?

EDIT:

Well alright, I'm not sure what I've done but it has started to work as expected. After creating my post, I found that PulseAudio is what's handling sound on my system.

Running

systemctl --user status pulseaudio

I can see it is running as a user service.

I modified the service file located at /usr/lib/systemd/user/pulseaudio.service to include the --log-level=3 flag, restart the service using systemd then run

journalctl --user -f -u pulseaudio

I was hoping I'd see more details when I plug/unplug things.

However, that is not what happened, instead, somehow that has caused things to start working correctly. I can plug/unplug any of my USB audio devices without causing the USB mic volume to reset to 100%. I've now opened my usual set of applications and tested the same circumstance, then rebooted and tried again yet it is still fixed. I highly doubt changing the log level on a service would fix the issue, maybe just restarting the service fixed it? I don't really understand, alas it seems to be fixed. Maybe someone knows why?

Last edited by mattboy9921 (2020-11-05 20:28:20)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,363

Re: KDE Audio Levels Reset When Plugging/Unplugging USB Mic

was it started when you checked first? Pulse is indeed what should and usually does properly remember volumes. If it wasn't started when you checked it might be that some other instance was started first using another volume database (quite unlikely though, this would usually be something you do consciously)

FWIW to increase the log-level of pulseaudio you'd append the startup command with varying degrees of -v for more verbosity so taking the service example line you'd use something like

/usr/bin/pulseaudio -vv --daemonize=no --log-target=journal

or so