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I don't know when this happened, but suddenly my KDE sound manager reported no device was found after a reboot.
pulseaudio.service and pulseaudio.socket all failed but the displayed reason didn't provide much information:
pulseaudio.socket: Failed with result 'service-start-limit-hit'
Then I tried pacmd list-sinks and got a permission-denied error. It could not access ~/.config/pulse.
It turned out that this directory was owned by root, and everything else under ~/.config was owned by myself. I know pulse should be a user service so I chown-ed it back and hoped it would work. The sound was back again indeed. (This is the right action to do, no?)
But why is this? How can I find out who ate my sound by polluting the permissions (especially after a system-wide update)? (I'm new to Arch but I've gone through a CS degree so feel free to tell me anything deep.)
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The usual cause of things like this is using sudo to run anything that writes to the config file
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FYI, I've had the same thing happen a couple of times, maybe once a month or so. After booting up my system, nothing will produce audio because my ~/.config/pulse directory is owned by root. chown back to my user fixes it, until it happens again. I haven't been able to figure out what causes it.
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