60 cycle hum

[MrStab]

If you tie the two pot lugs together, it would fix this problem without having the replace the pot.

good call, i didn't think of that.

if you put a 470R resistor or something (you could measure the resistance right at the edge of the "safe zone" before it screws up for a more precise value) between lug 2 and the rest of the circuit, and that doesn't change anything, then it may count as more evidence towards a bad pot.