On my system, if I turn off system power without doing an emergency stop (track power off) first, it will start up again with power on the track ready to go when I turn system power back on. So if that's normal, the handhelds shouldn't be flashing, etc.

I have seen elsewhere that when the system battery starts to go flat, various weird things start to happen. It might be worth opening up the box and changing that to see if it solves you problem.

Good luck! Mike