Buzz or Rattle Noise In Headliner

I have deducted that the vehicle needs to be outside long enough for the roof to heat up from the sun. Then if the road is rough or I hit a bump or pothole, that produces a buzz or rattle in the headliner. Sometimes the stereo will also cause this noise.
If I tap on the headliner just behind the sunroof or at the edge next to the rear window, I can clearly hear it. Any ideas what might be causing this noise?




I will be taking her in to get this covered under warranty; anyone know the exact TSB on this?



