I have a Alpine 9856 HU mounted correctly in my 2007 Chevy ex-cab with two 12's down firing and when it hits on hard notes the cd skips. It seems to jar the entire dash, also the truck has rubber floor instead of carpet. I was planning on building a box to point the woofers up but if anyone else has a fix please help. I have already sfuffed foam all around the HU.

Thanks, Scott