Since I’m trying to do a parts-on-hand build, I’m using a rotary switch I pulled out of something. It’s a 4 position switch that I will be using for the speaker impedance selector. My OT has 3 taps, the switch has 4 positions. Not a good idea to flip it to #4 and have nothing connected there. What could I hook up to that 4th connection to keep the OT safe should someone flip it to that position?