So i have the Harmon Kardon option on my car. The rear deck is known to rattle, because basically things get loose with time.
So i took off the rear deck subs(6x9's) with a 8mm wrench. Then i took a small hand towel and stuffed in evenly into the rear deck speaker area(under the rear deck between the frame...and holy shit.
no more rattle. easy fix. ten minutes.
so if you have a rear deck rattle with harmon Kardon premium...just stuff a towel back there.
make sure you put it in front of the sub woofer holes, otherwise ull muffle the sound.
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