I have been noticing some speaker or subwoofer distortion coming from my late 2008 MBP. It is most evident in Adium when I receive or send a message using the default sound set and the volume up past half. It seems to be a resonance that is transmitted through the chassis of the laptop. It's reproducible with certain music as well, but it is most evident with the Adium sounds. I'm not near an Apple store to check it out, so can someone maybe open up Adium and send a few messages at full volume to see if there is this rattling/vibration type sound? Placing pressure on the chassis at different points with my hands helps to alleviate the issue partially, but it's still there. Thanks!