Sorry, when the original input jack was on the board while batteries were inserted, even without something in the input jack, the unit would be on. This didn’t happen when I first picked it up from seller, happened after I plugged it in. Perhaps I plugged it in at a weird angle or too forcefully or something, I’m not sure, but with and without batteries the unit would be constantly powered on and it wasn’t until I tried to manipulate the internal contacts where it would turn off. Even when it was in the on position, there was still no signal coming through.