[MFury]

I still havent figured my noise out. It appears to be coming from the back of the car, but I have tried lowering/raising the headrests and I have made sure those clips for baby seats are properly closed. It sounds like a vibrating plasticy kind of rattle but for the life of me cant figure it out.

Get someone to sit in the back and try and locate the noise while you are driving. Or have someone else drive (I know its an absurd notion to have someone else drive) while you locate the noise in the back seat.