Hi I recently brought a 2011 730d M Sport with 45,000 miles on the clock, after a few hundred miles I could here a slight whining noise coming from the engine or transmission, I have had the car in at my local dealer on two separate occasions and they say there is nothing wrong with the car, engine or transmission and that this whining noise is a characteristic of the 7 series? I spoke to BMW who advised the same? I then took the car to an independent who was trained by BMW and he says its no normal but ruled out the transmission as the noise comes when rolling in neutral? Does anybody have any experience with this model making a whining noise, any ideas welcome? Thanks, Gareth