I took my MBP in to the Apple store a few weeks ago because of this. Basically, on certain songs, sounds, etc. the right speaker will sound very distorted. The best way I can describe it is it's like playing sound way too loudly through a speaker. Very annoying. It's also hard to explain the type of sound triggers it.. but if I turn the balance all the way right and find a particular part of a song that does it, then replay that segment with balance to the left, it sounds fine. The TokyoTrainStation sounds for Adium seem to do it. What should I do? I already had the speaker replaced (I couldn't tell in the Apple store when I tested it because it was too loud), but this doesn't seem to work like it should.