[Accord Man]

Howdy!


Add mass(weight) to that panel..


You could use a sheet of Dynamat or Brown Bread..

Otherwise, spray an asphalt based undercoating type product on the panel.. Do so from the inside.. obviously..


Your local Pep Boys or Canadian Tire, depending where you live, should have the asphalt undercoat spray for a couple of bucks.. It works great in non-extreme cases.