The audio sync group functions let you play multiple sounds that
start at exactly the same time and stay in sync (on a per sample
level). This enables you to (for example) add various tracks for a
single song and then fade in and out sections without having to
worry about whether there will be any delay between them. Note that
these functions currently only work with compressed audio,
ie. *.ogg and *.mp3 format files.
The following functions exist to deal with synchronising audio tracks: