This is technically possible.

Problem is trying to define what events get triggered when you engage and disengage. You could begin music with a battle hail, cue music, then end music with a death. Though a lot of possibilities exist for defining engagement/disengagement, unless you want something very specific, it's hard to apply a broad case scenario.

If you look on voupr.com CrazySpence made a parsec music plugin, you could use that as a code base for trying to override VO's native music. Others have made similar things, but I can't be bothered to search for it right now :P