He would probably just, I don't know, turn it off.

No, because that would make too much sense!

Passive agressive

Sometimes it's easier to be the nice guy....

Having music turned off, or just down, hardly makes someone the bad guy! I'm sure OP would turn his music down for the roommate too, that should be the upside of getting on well. YDI OP, common sense would would've been to nicely ask him to turn it down, like a normal reasonable person would. Your fault if you fail now. And I'll laugh. Bahahaha.

Actually, OP is a girl.

I think OP should have asked too. Worst case is that the roommate says no. Headphones are a great invention too lol

When my husband practices bass too loud, I ask him nicely to turn it down. He either does or uses his headphones. The only time it caused a fight was when I was having a bad day and didn't ask too nicely. Most people, especially those you get along well with, would understand the circumstance.

OP couldn't exactly ask someone who isn't home, to turn off their music. Unless she asked before he left, asking someone who isn't there won't help at all. On the other hand, in her attempts to get his attention she likely would have realized he wasn't home, which is probably what happened.

Shock-and-awe that thing.

No, blare yeti porn at full blast!

It wasn't even his fault... OP could have turned off the music