thats what my guess is, i think we need to tighten the bolts down better...
i didnt get it professionaly done cos i was being cheap!
dual is not bad for the price i got it and especially for what i replaced.
the dude had chrysler speakers in my elantra! and some 80's tape deck...so its an improvement now for sure although i want to hit up some more bass but the rattling sucks!