New class (AS3) I wrote which I'm willing to share. However before I'm posting it to the bbs, I need a place to host the demo so this has to get past judgement :]
Basically, you can use it with just one line of script to create, and one to update the "position" (which in the demo is the red line).
This would be EXTREMELY useful in games were the music has to change according to the environment.
edit: If the audio is not synchronized (which happens only very rarely) just hit the friggin' F5!