Blower motor speeds up and slows down only in second speed and only on vent setting, only when you accelerate. Dealer will not fix as it only does it for me. But they did hear it after I asked a mechanic to join me for a ride.They then determined it was the blower motor and replaced it. It still did it and still will not repair it as they claim they don't know what is causing it and won't do it for them.