VPI JMW grounding issue

Not sure where to post this, so I'll try here. my VPI JMW Memorial tonearm has developed a noticeable hum. The hum increases when I touch any part of the tonearm, so I'm assuming it's a grounding issue. I've swapped cables, (except the leads from the cartridge), phono preamps, and cartridges, with no improvement. Is there an easy fix that I need to know about? Is there a service that will rewire/upgrade the internal wiring? TIA for any assistance.
If you have access to a amp meter, you can check continuity of the wires in the arm tube and loop to junction box. It sounds to me one of these wires is making contact with the arm tube or box.
Hi, this thread is old, but with my new VPI table and Lyra Kleos cart since Friday, I'm having what appears to be the same issue--did you resolve it?