I recently installed a Pioneer AVH-P3200BT with the correct wiring harness, and chime harness. I could NOT get the steering wheel control to work. (installed in an 06 Chevy SSR)
Anyway, the first trip I noticed that the unit would not output sound until the vehicle got physically warm inside. The unit comes on, and and the display lights, and indicates volume, channel, what's playing, etc.
I'm out with the vehicle for a week, and every morning same thing. I can hear the relay closing (a power relay as part of the harness - I hear what sounds like a "pop" in the rear speaker, and no sound.
The sun beats on the vehicle, and after an hour or so, I turn on the unit, and everything plays normally.