[Smoove1010]

I'd check every nut and bolt in that general area. I'd also check the rear wheel bearing - jack up the car, take off the wheel, the caliper and the disc. Put the car in neutral, spin the hub, check for play. I had a rattling sound on the driver's side, turned out that the wheel bearing was so shot that when I did this test the hub actually wobbled around.

Good luck!