Does the pioneer AVH-P5950DVD have a input for a steering wheel interface? I have a 2007 325i M-Sport and the stereo shop has fitted a interface to retain the steering wheel functions and parking sensor audible tones, however, I was informed that this unit does not have the input on the rear of the unit for the interface. What is the recommended interface for this vehicle and stereo to retain steering wheel functions and park sensor tones?