my on/off switch gave out on me or so i thought so i got a new one and hooked everything back up and when i plug the power into the RX the batteries instantly start to get hot and nothing works. i tries it on another RX that i had and it did the same thing. the battery holder that i have is the kind that you just put 4 AA batteries in. i cant find any shorts and it still does it even without the switch installed. why is it doeing this? i know next to nothing about electricity please help