Proto Sound Northern doing strange things

I pulled my MTH Rail King PS-1 Santa FE out of storage and ran it this morning. It seemed to run fine until I pressed the whistle button, then it stopped. The head light still shown, my meter told me power was on the track and the whistle would blow. Hitting the direction button moved the engine to neutral and another push on the direction button put me in reverse. The engine preformed quite normally until I pressed the whistle button again and it stopped. I left it on the track and gave it a couple of hours of charge at 11 volts and it seems to have cured itself, anyone have this problem?

Since it is Proto 1 I would suggest a new battery, unless recently replaced, or even better invest in a BCR. If this is an original it might not hold a charge for long.