This is rare so it's hard to diagnose. It only happens on occasion when I'm stopped and have the brakes pressed. I could put it in park and let off the brakes and it goes away. I'm guessing something with the exhaust system transmitting vibrations through the car. It feels like it's right under the back seat. I checked the muffler hangers and they looked good. I didn't have the car high enough for anything else. I really need to get under there and make sure everything is tight.

Did anyone else experience a similar problem and if so what was the cause of it?