Eliminate Rattling Sound from Sub?

[superezra]

So i'm going to upgrade my sound system soon, but i'm sure the issue will remain even with a better system. When I put the bass up the boot rattles hard, from the inside it sounds alright but from the outside it's just ugly. I'm planning on buying dynamat and covering the boot, but has anyone used other alternatives? Or if you've used dynamat, what other places would be good to stop the rattling?

[Taz]

ive jammed foam cubes into the boot lid areas where the metal can vibrate under heavy bass, secured the parcel tray down nice and tight and have my sub angled slightly upwards away from the front of the car, sounds mint from the inside, really dont care from the outside

[superezra]

So is vibrating a common issue in FTOs? The vibrating seems to come from the bottom part of the boot, not sure what it is though, the spare tire is tight.

[kiz]

I had the same problem in my Mazda MX6. Just fill it with dense foam as said above, simple enough, if it doesn't work then you didn't use enough haha

[payaya]

You clip in your rear seat belts? They rattle the panel they lean against.

I used 13 square feet on dynamat and it didn't do much imo.