ALSA software mixing doesn't seem to work
I have a computer which has on old soundcard which doesn’t support hardware mixing. ALSA is able to detect this and thus tries to use software mixing instead when I try to play more than one audio stream at once, however, software mixing doesn’t seem to work out of the box on AlpineLinux. When I try to play more than one audio file at once with mpv I get the following error:
ALSA lib pcm_dmix.c:1007:(snd_pcm_dmix_open) unable to create IPC semaphore [ao/alsa] Playback open error: Permission denied [ao] Failed to initialize audio driver 'alsa' Could not open/initialize audio device -> no sound.
If I mpv as root (which is not the kind of thing I want to do) the issue disappears and the user I am running mpv as is in the audio group.
(from redmine: issue id 6405, created on 2016-10-28, closed on 2019-05-06)