An update:

I removed the washers (described in my last message), cleaned the connectors firmly (both the sleeve and the empeg) with alcohol and Q-tips, and cleaned the casing and the inside of the sleeve with alcohol. As before, the problem is gone for now.

The next time the problem comes up, I'll try just cleaning without any dismantling or fiddling with the unit and see if that solves the problem.

Question: Is it important for the empeg's casing to ground against the guide bumps inside the sleeve?

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Tony Fabris