I wonder if yours is newer than mine.Odd I have never had batteries in mine from day 1 (have had it for 5 or 6 years). External pack only. No extra key presses or unplugging and plugging in for me. On and Off.
I really don't worry about the little quirk of mine as I have AC on pur firing line , and I just run an extention cord to the power pack , and plug the power pack into the unit .
I rarely useciyvthese days anyway now that we have our Shotmarker target as well. Except for my BP guns....
Cat