For those who have mounted a sub on the tailgate, any pointers on getting rid of vibration? I’ve got a pretty nasty rattle going on at higher volumes and it’s getting worse. I have a layer of dynamat between the sub and the tailgate and it’s well secured. Best I can tell is the rattle is coming from the trim pieces. Any thoughts on how I can kill the rattle? Please talk to me like I’ve got the skill set of a 5-year old. Thanks in advance!