Raammat60!!
I just finished putting down Raammat 60 (similar to dynamat) throughout my entire car> What a difference!!! Everything is a lot cleaner and clearer. It was a real pain to strip the car down to nothing, put the mat down, and then put everything back together, but it was worth it. The only thing that rattles in my car now are my teeth.
I highly recommend this product for anyone looking for clean sound.