I have a problem when the car is cold the stereo turns on but the antena does not come up and no sound. I heard the ampl click but no sound. However. after 30 minutes or so, I turn the system off and on again and sometime it works. I finally hear sounf and the antena comes up. When I turn the integrated cell phone, the antena comes up all the time. I know is not the antena. Could it be a relay that is faulty? Any Ideas?