Music Player Daemon
Install, then run as user with all configuration files in ~/.config/mpd/.
Go down config list, copied from /usr/share/docs/mpd/ or something.
I couldn’t change volume, so in mpd.conf I uncommented the pulse audio lines and restarted mpd. This allowed pulse audio output, which allows volume change via mpc.
Also, make sure the user mpd is part of the group pulse:
sudo adduser mpd pulse
In the audio_output section, try setting the mix_type to “software”, not “hardware”.
If you’re using alsa, check if the mpd user is part of the group ‘audio’.