My 530i with Nav seems to lack the ability to control audio system volume based upon spped of the vehicle. When I got curious about this, I went to the dealer and requested a Radio manual. It tells how to control this setting if you have the standard radio. The "new owner's" CD also shows how to control it from the MID. The section on Nav doesn't talk about Speed Volume Control. The Nav manual doesn't list this feature in the index.
Does anyone know how to control this feature? It seems illogical that it would be missing just because I paid another $2000 for Nav. Thanks, Colin