my Rega RP6/Exact does not hum when in my upstairs system, but I've brought it downstairs and there's a strong hum. I've googled the problem and people have suggested running a wire from the tonearm body to a ground. Haven't tried this yet. I also brought a Chromecast Audio down and when running out of it's analog output, I get a strong hum...but if I go optical out > DAC, it goes away. Any ideas? Are the two possibly related?
Have you taken it back upstairs to see if it still hums? Moving it must have changed something. Check all your connections, then check them again.
It's hard to say without knowing exactly how many things you have connected together and how, but I would start by disconnecting everything from the amplifier except for the turntable (and speakers, of course) and see if the problem still exists.
I have moved it back upstairs and there is no hum. Seems to be something in the AC circuit in the downstairs. My digital source in the same rig sounds totally fine. @BostonBob that gives me an idea. I'm running an external phono preamp, but the integrated i'm going into has a phono stage. Maybe I'll try taking the external stage out of the loop and see if it goes away.
The latter suggests a ground loop between the chromecast device and the DAC. The former could be a lot of things, but if that's where you're running the external phono pre, could also be a ground loop. IIRC Rega tonearms are grounded through the shield of one of the tonearm cables so adding another ground connection for the tonearm body likely wouldn't be helpful. @BostonBob has describe the right troubleshooting procedure -- unplug everything from one another and from the wall power, then start adding components one at a time -- amp to speakers, is there hum? dac to amp to speakers, is there hum? etc.
