This same reason brought me to this site! Welcome, from a newish member to a newbie member!
Its the blow motor / door actuator for when you swap modes on the Climate Control.
Theres not much you can do besides remove the door IIRC, untill it craps out. My Jeep only does it when its really cold outside. It hasnt done it at all this year and weve had temps in the 30's. I did add the cabin air filter kit, dont know for sure but it seems to have helped the problem.
Like I said, not much you can do about it right now, dont worry about it unless you start losing air flow/temps arent what you want.