Quoted from RoberAstur:You mean when you leave the multiball by hitting mist and enters the video mode ??? In that case, the machine has not had time to recognize the mist multiball. It is a common misconception.
Probably this. If you were in an extended multiball, and it started video mode, I'd think something is wrong, not that it's a bug. Never seen it other than hitting the mist ball into video (in which case, if you die fast enough, you still get your mb).