Comment 19 for bug 210472

The only clean solution to this is to run pulseaudio in system mode and add the timidity user to pulse-access group. This also fixes some other problems pulseaudio has and effectively stops other apps from grabbing the soundcard.

This is because by default only the current user, which is also running the pulseaudio daemon, can play audio. By switching pulseaudio to system mode, it can be access by every user in the pulse-access group without starting anything before.