derrickonline

First off, I have 24" on my Q7. That's not the issue. I kept hearing rattling and determined it was the rear sunroof.

I have the big sunroom (whatever they call it). The smaller rear sunroof rattles.

If I press the button to "pop up" the rear sunroof the rattle goes away.

So it's as if when it's down, its' not being held the weight of the sunroof keeps is keeping it down so it rattles a bit.

Try driving when you hear the rattle pop the sunroof up and see if the noise stops.

Once thing I noticed about Audis and VWs...always the strangest issues that I've never experienced on any other car.

Leaking sunroof drains
AC leaking inside the car
Torque seal converter
Transmissions sensor

Never had these issues with ANY car. My VW Phaeton, it was like an arcade game whenever you started it up. What light or alarm is going to go off today.

GKP1

After months of taking out components (tonneau cover, jack, etc) trying to diagnose a rattle I ended up driving around with someone sitting in the trunk to pinpoint where it was coming from. The rattle was coming from the rear sunroof. Like one of the other posters, when the rear sunroof was up the rattle went away. After a week at the dealer, they ended up replacing the entire sunroof frame. The rattle is now gone. Makes me enjoy driving the car again, rattles make me crazy. With some effort, got it all covered under CPO, cost me $85.