Static electricity: Unique to Vinyl Systems?

Most likely.

Did you also replace tonearm? You'll need to check ground path if there's continuity.

Marakanetz

The problem was noticed with my old vinyl rig, which was a Rega P-5 feeding a PS Audio phono pre amp. First I changed turntables (Clearaudio Concept mc, new tone arm), then changed to a Jolida phono preamp.
The reason that I changed was a loud transformer hum in the PS Audio (I decided to change TT because I wanted to move to a mc setup). The hum is fixed but all this other stuff is still there, and for the first time I've noticed it occurring when no records are playing.
I'm realizing the one thing that i haven't changed is the power cord (SHunyata
Hydra). I will change that next, but I'm wondering if it is a static issue or something with the main, although it doesn't affect the digital sources at all.

Sounds like pickup of RFI (Radio Frequency Interference) to me. Try turning off all fluorescent lights, including compact fluorescents that fit in incandescent fixtures, as well as all dimmer switches which may be in the house, and anything else that could conceivably be generating significant RFI.

Regards,
-- Al

I agree with Al (airborne rather than system borne.) In addition to the sources of RFI he mentions, I'd like to add two more: (1.) the power cables on ANY digital equipment, and (2.)the RFI created by static discharge such as people walking across rugs/carpets, clothes tumbling in the dryer, etc.

It is important that power cables used with ANY equipment containing digital processing circuits (even if it's just a digital display) are well shielded. And that the associated outlets (wall or power conditioner) have filters that drain 'digital hash' to ground.