Airsonic-Advanced: Playback fails to begin for most tracks

[dweymouth]

This is likely the same root cause as this issue in my project - also an MPV-based Subsonic client - which I discovered testing with airsonic-advanced (I personally use Navidrome and this has never occurred with Navidrome.)

Repro:

1. Spin up an airsonic-advanced server against your library using the latest docker image, running on localhost (see here, I used the docker cli)
2. Add the airsonic-advanced server (http://localhost:4040) as a music provider in Sublime-music and connect
3. Try to play back any song, most of them may fail to play

Edit: I'm not sure if this is codec-specific - 99% of my library is FLAC and that's what I tested with