I have an '03 G35 coupe with the Bose and Nav. Once in a while when I'm driving the radio goes blank and I can't change the station, turn the radio off or on, or even adjust the climate controls. I can however control the radio from the steering wheel controls. Then as I keep driving it may just start working again or it may not work until the next time I start the car. Does anyone else have this issue?

 

It's a commpm issue. there are several threads about it. The common circuit board shared by the AC and radio is going bad. the board will eventually fail permanently.