Since the camera phones are black and made of glass and sit directly on the windshield, overheating can become an issue. Overheating stops charging, destroys the battery life and of course shuts down the phones and broadcast. I have mine positioned directly above the defrost vent and run the air conditioner to keep them cool. This is why you hear a breeze or rumble noise on the broadcast. During extreme heat the cameras will shutdown if I am stopped for the afternoon or fuel with the engine stopped.