I dont know about the cold living in Miami but mine whistles too I think it may have to do with the radio. I remember back in the day if you did'nt ground the radio properly you would hear a whistle sound from the speakers but Im not sure the sound comes from the speakers or not? I agree it does sound cool maybe it has something to do with the rocket car in the commercial!! Some sort of sublimatable message! Make us think we have a Rocket Truck.

Later!!!
VZ