I’ve not long received my new F90 M5 and I too have noticed something funny with the speaker setup. If the fader is in the middle position the front and rear door speakers can be heard but if you fade to the rear all you hear is the rear deck speakers which are very faint, the rear door speakers have no sound what so ever coming out of them.
BTW this happens regardless whether the Radio is in use or anything else, if this is indeed normal then I wished the bloody car have came with the standard BMW setup instead.
