My drive's side ventilated seat was making a loud compression noise (almost sounded like a vacuum was on). Technician said it wasn't normal and referred to the sound as a "jet engine." Turns out there was some foam/fabric blocking the fan below the seat.

Hope that helps anyone else with the same issue.

 

Good thing they found and fixed the issue.

btw, its a simple fan that blows air through channels in the foam. That slightly pressurized air migrates through the foam and has a cooling effect. I love the feature and wish it come on the tech model