I was getting a "plastic on plastic" rattling noise from the sunroof area. It didn't take long to figure out what was going on and how to stop the sound.
The plastic finger grip knocks against the plastic trim of the headliner when the sunroof shade is completely closed.
Pulling the shade back a half inch keeps the two plastic parts from touching and stops the annoying noise from the sunroof. The edge of the shade extends about an inch past the hand grip cutout, so moving the shade a little doesn't let light in.
It seems obvious once you see what is going on; but it only happens while the car is moving. It's hard to figure out where the sound is coming from while you're busy driving down the street. I figure people with the same issue might search the internet for a solution and find this post.