I often get the same compressor noise when starting the car. It would make sense that it's for the suspension and I wouldn't consider it as anything wrong.Sorry for late reply!
Dealer says it's the compressor for the suspension. Which does make more sense to me than heat pump. Because I typically hear it soon after starting the car.
Whereas I tend to use preheating alot and nowhere near these levels of noise.
Could be my impression, but more/longer noise when car was parked on a slight slope.
No resolution for the noise however.