Ok, so my battery is dead after a couple of days.
No cable plugged in, but battery connected.
When measuring battery poles in the batterycompartment, i reads 480 kOhm.
No surprise it consumes battery, even if the guitar is hanging on the wall.
My workaround:
Unplug battery. Turn it upside down.
Face battery poles towards bottom of guitar. (Opposite direction)
Then You can close the lid, with battery inside.
All other directions will not allow lid closing.
/Lasse
Sweden