I recently replaced the Air Mix Motor on the driver and passenger side. Before they completely failed I would hear crackling sounds from behind the dash and they are gone now. The climate control now works flawlessly. However, I'm hearing very similar crackling sounds coming from the rear climate controls -- right where the center storage area is located. I suspect there is another Air Mix Motor somewhere in there, but I haven't been able to find any discussions on replacing it here or on the internet. I am wondering if anyone here knows if there is an Air Mix Motor in there, and if so, the part number for the unit. It would be ideal if there was a write-up on how to replace it. Thanks!