That original type of ball popper was prone to the roll pin working its way out of the armature. Often, while it was part-way out it would snag the blade of the 'fork' switch and cause false contacts, e.g. running a 'Match Up' on Earthshaker without a ball having dropped into the shelter/subway, or registering a lock and serving out another ball. Though I don't recall ever getting a multi-ball release on F-14 that way..