I just finished my 4cuft sealed enclosure for the dayton ultimax 15. I'm using the dayton 1000 watt plate amp to power it. The problem im having is a rattle from the driver area when played loud at low hz. Somewhere between 30 and 35 hz. I only occasionally hear it during movies but it is very noticeable when doing a frequency sweep. Could I be just overpowering it or is there something else I can check?