I have seen one of those Volume Control/ Switches with what seemed to be a second wiper. But I never pulled it apart to examine how it worked internally; You could pull it apart. What do you have to lose?? It is already broken as to the switch itself! I had a similar problem with a Cdn. Westinghouse volume control/switch. I pulled it apart but could not fix the switch. So I simply disconnected the leads to the switch and hooked up a tempory On/Off toggle switch until I find another/proper Volume/On/Off switch. The problem with taking the switch assembly apart , is that you must drill out the rivets (usually two). You may get lucky and find that it is just a bent stop caused by someone using brute force. If that is the case all you may need to do is just re-straighten it. However in reassembling it you may not be able to use screws to put it back together. As I said, It is already broken! Nothing to lose!