[Dons his referee outfit and outstretches his arms]
TIME OUT!
The terminology (AI vs. Trigger) is a moot point if the event you are trying to describe is not reliably documented and reliably repeatable.
What I do know:
The "I heard weird music" syndrome is a common report all over B.net. What is uncommon (and I think nonexistent) is a report that actually cites either:
1) The name of the music track as it appears on the Official Soundtrack
2) The fact that the track does NOT appear on the soundtrack
So... a list of all the tracks that DO appear in the game (and where) would be most useful.