Does anyone know what would intermentaly cause a humming sound when slowly reversing an e46 and pressing the brake pedal? I know it's coming from the rear of the car, it only happens sometimes, and this is the last issue that I have to fix with this car. It's annoying and it's been happening off and on since I bought the car. I checked the rear brakes and they look good, any suggestions?
This video shows the exact sound I'm experiencing with my zhp.
http://m.youtube.com/watch?v=HwV2rZ5B4s0