Quoted from RobT:I have never, ever, heard of this happening. Was this a pin on route I assume? Drop targets not dropping on ACDC is surely not a common problem by a long shot.
It happens on mine all the time also. Mine was NIB purchased 7 months ago. I try to hit the middle of two targets. That seems to help make sure they drop and also gives you two jackpots if they are lit. For some reason, waiting until the canon is coming back up from the bottom seems to help as well.