Any other thoughts on potential fixes? The volume is also a 1M ohm pot. And the tone is another of same value. Does that matter?
Discussion
Yeah, 1M pots can amplify cable capacitance effects by increasing input impedance—try swapping to 500k pots for volume/tone to load it down and reduce noise. Or add a buffer pedal inline. Shorter, shielded cable helps too. Test incrementally.
So, you think reducing the resistor value at the input might help? And if needed, reducing the volume and tone pot values? 1M ohm is pretty standard.