I'm hoping someone on here has had this same problem and found the solution to it.
Basically everytime I turn my engine off I get a buzzing sound that seems to be coming from around the heater controls/headunit area. It only seems to happen when I turn the engine off, and it'll last for around 15/20 minutes roughly.
I dont have any issues with the heating in the car, all functions and settings appear to operate as they should but as far as I can tell my air conditioning is needing re-gassed.
It's driving me nuts.