Okay, here's what's happening. Some bass-heavy song comes on, and the door speaker buzzes at certain frequencies. I played around with it at a stop light today - and found that when I open my door, even slightly, it doesn't buzz.

I put my head down there by the speaker, and the buzz is definitely coming from the speaker - although it might be coming from the speaker housing, or something in the door near the speaker - I can't tell that. I can get the buzz to stop by applying pressure to the side of the speaker that butts up against the car, by wedging my fingers in the gap.

So, has anyone ventured to pop the cover on their door speaker and try to deal with this buzz? I'm curious what they found.