I have had quite a few Wizards. I had this issue on two of them and fixed them both. It's an easy fix. The jacks have a double tab on the sleeve side. These are switchraft shorting jacks. The shorter tab needs to be slightly squeezed against the other tab so it makes contact again. I used a needle nose and a screwdriver. You can see it here. That shorter jack isn't making enough contact which caused the same thing on two of my Wizards in the past. If you separate them and then bend the shorter one very slightly toward the longer tab you should be good. I did it easily without removing the jack.