I am no two stroke expert, but I believe that indicates that one of the crank seals are leaking. Letting in unmetered air and it continues to pull in gas through the carb even with the throttle closed. Someone with intimate DT knowledge can probably even tell you which side it is, as I recall one seal goes to the transmission, the other does not so that's probably the one leaking. Why this happens even with the ignition off, I can't tell you. I have heard of it happeing and I'd like to know why myself.