Rattle my brains

[Len 911]

What is located under this part of the rear pillar. Under the headliner between the quarter window and rear window. I have a rattle that sounds like it is coming from this section on the passenger side. It only does it at a certain vibration , if I give it more or less gas the sound goes away. It is not constant just at certain vibrations. What could it be ?
Not my car but a pic of the section I am refering too.

[Len 911]

Anyone, Man you guys usualy respond in two seconds. i know it is an odd questions but I looked for pictures and cannot find an awnser. Please help me this noise is puzzling.

[Quicksilver]

Maybe the sunroof drain is vibrating? I'm not a body guy but that is the only thing I know is in there.

[Todge]

I had two clips that were on the outboard side of the sunroof, almost parallel with the doors. They rattled and it sounded like it was coming from the back, but they were directly above the head.