I have a 2000 DTS...and i keep my treble, midrange and bass 2 down from thier max setting on my radio. Sometimes when i play certain songs with certain bass frequencies the subwoofer vibrates my back deck. The music dosnt have to be loud either...it can be smooth jazz at a medium volume and the back deck (i think thats the problem) with vibrate. It wasnt a problem at first but now its really really starting to annoy me. My car is in for warranty work to fix it because im sure cadillac didnt make thier DTS to vibrate when u played music. Just wondering if anyone else had this problem and how they solved it?