millercarbon:
So now at last we have our answer: worn internal wiring. Probably internal and out of sight but carefully inspect all you can see. Use tweezers to pull the cartridge clips, or at least give them a little nudge to confirm they're still nice and tight.
But basically yeah, probably time for service. If you like the arm they probably can upgrade the wire. Origin Live has wire upgrades for theirs, SME should too.
A pop to me is more of an electrical kind of thing. But all the electrical glitches I've heard in situations like this the sound cuts out it doesn't pop.
So now at last we have our answer: worn internal wiring. Probably internal and out of sight but carefully inspect all you can see. Use tweezers to pull the cartridge clips, or at least give them a little nudge to confirm they're still nice and tight.
But basically yeah, probably time for service. If you like the arm they probably can upgrade the wire. Origin Live has wire upgrades for theirs, SME should too.