Hey Peter,
It would be unusual for a potentiometer to actually "go bad", particularly those used by Alembic. No corners are cut with their choice of components. Furthermore, at least on the Series models, the pots they use are sealed and self cleaning. Meaning, they DO NOT encourage the use of spray cleaners or lubricants. Those chems may fix things temporarily but introducing any "gunk" could lead to later problems.
Having said that, sometimes pot noise can be caused by other components failing and leaking DC current into the audio chain where it is not meant to be - even from the amp's input side of the cable. You'd need to dig deeper to know if that's the case here and I don't know enough about the Epic circuitry to know if it's even a possibility. Maybe somebody can chime in with other ideas.
One way or another I'm confident you'll get it sorted out.
Jimmy J