There is a grinding noise coming from the right interior side panel next to the 3rd row in the back seat. It almost sounds like a fan is grinding against something. I thought it might have something to do with AC but it does it even when the AC is off. It also occurs sporadically. I won't hear it for a week and then It'll happen 3 days straight. I could really use some help here.

2005 Chevy Suburban Z71