No, I fixed Soopa's car at the TL Meet in NJ. He had the same problem.
Open your trunk lid. On the sides of the trunk lid are two rubber stoppers. They are threaded so as you turn counterclockwise they come further out.
Turn them out a little bit and then close your trunk. Crank up the tunes. If it still rattles, turn it a little more until the rattle goes away.