I hear the same noise on mine. Not sure if I would call it "growling", but definitely somehting is going on when I unlock the doors. I really only hear it when I unlock the doors in the quiet of my closed garage (it isn't really audible in an outdoor parking lot). I have been driving the car around since October 29th and whatever this is, it hasn;t apparently caised any problems. I will ask the dealer next time the car is in, which should be next week, for a checkup.