stop the rattle

i have 2 kicker subs in my trunk (12 in) they are loud as hell inside but rattles on the outside does any body have ne cheap suggestions of trunk lining or something i put my back seat down trying to let the sound out of the trunk but i need something better

I suggest u add a license plate frame frm dynamat frm sounddomaun.com its only 9 bucks and i wuldnt doubt if alot of your rattle are coming frm ur license plate....

well you can use insulation tape for the license plate. Also 99cent cans of underbody spray, apply multiple thin coats.just make sure the place you're spraying is clean and only use it on metal duh...