call the cops and tell them you suspect they're using drugs
I agree with American Sensi...
Calling the cops is a bad idea, and not likely to result in much that's good...
it all comes down to a question of just how much you want to f*** up their lives...
spend a little while smoking roll ups with card roaches in them, leave them below their window.
go buy some pot,
wait till they've left their window open one day...
through in a ball of pot so that it'll land on the floor just in front of the window (looks like it's been blown off).
then go burn some pot outside their room to stick up the hall...
call the resident tutor...
laugh as they are expelled.
the continue to not be allowed to play your music.
that's harsh though.
Of course you could always just do the same as they are going. just go and complain persistently about things that they are (or are not) doing...