I just got this '98 Fender American Deluxe Jazz Bass and it's great except for one thing... When the pan knob is centered, the whole tone just goes kaput; like it just went passive, except with some tone control. When the knob is slightly turned off centered to either PUP, the tone returns; however, you only hear that one PUP, no blend. There have been no mods to this bass. What I've done to troubleshoot: 1. Checked all grounding wires. 2. Checked battery. 3. Looked at wiring, it seems correct compared to the OEM diagram (nothing came loose). Can a pot just die?