"We'll not risk another frontal assault... that rabbit's DYNAMITE!"
this. if you have a projector or can borrow one just aim the image over his area or agaist the wall he is on.
OP you need to step up your game. My friends who have spent time turning wrenches in dealerships have stories about like filling people's tool chests with grease for being douchebags and stuff. Having a nuclear arms race over who can play ****ty music the loudest is only going to piss everyone else off, and then you will be the one with a tool chest full of grease.
Let air into his brake lines just a little bit to scare him. It leaves no evidence and isn’t as drastic as cutting the lines.
MKV R32 # 3116 aka The Blue Rhino
It's passive as hell, but I think it could work.
Try to get a feel for what music he likes.
Start talking music with him and mention a few bands he might like that you're into-- like you're doing him a favor and just want him to experience this great stuff.
Burn him a few CDs of music you like that he may also like.
Have him listen to it.
If he hates it, go back to step 1.
Repeat until he's listening to the music you can stand and he has a new appreciation for.