I have a Fearful 15/6 built from lightweight composites by Art of Noise. I am powering it with a Fender TBP-1 and a Crown XLS 1500 in a rack case. The problem I have is that this cab vibrates quite a bit. I assume that is due to the light weight. So my amp rack rattles like crazy. I have tried a heavy anvil style case and an SKB case. I just get different types of rattles. Anyone have suggestions on how to prevent this annoyance?