towel in door

[Wren57]

Hey guys, I recently put in my infinity perfect components and mounted the x-overs in the doors (between the two pieces of metal). I used fatmat (dynamat copy) on the entire car, but my x-overs still manage to rattle against the inside of the door during heavy bass... I was thinking about getting an old towel and just shoving it in the door between the two metal pieces, not just behind the panel... is there any downside to this other than being ghetto rigged? but hey, who would know

thanks