Ok this is the 3rd time ive been havin this problem. I own a 2000 Cadillac DTS. and i dont know what the problem is but either the back deck is loose and vibrating, the subwoofer is blown or there is some metal inside the housin that is vibrating everytime i play a song. Its quite loud. The first time i took it to the dealer they replaced the Bose amp, the 2nd time they said the speaker was blown and replaced the subwoofer. The problem seems fixed then returns just a couple weeks later. Has ANYONE else had this problem? I dont know what kind of cheap shit cadillac is usin in thier cars. :annoyed: ..anyone have any input? Should i take it back to the dealer or have a car audio shop check it out first?