Ground Hum with Rega RP6, Exact and TT PSU.

" Sfall mentions to lower the gain which It is already done. "

Its probably still a gain issue. The Exact puts out 7.0mv. Just to give some perspective, a very common high output cart like the DV10x5 puts out 2.5mv. Most likely, nothing is broken, you just have a mismatch. Your dealer probably didn't say anything about it because its a package deal and they didn't want to lose the sale if they told you it would be necessary to buy a phono pre as well.

Call your dealer Monday and tell them the cart they sold you puts out 7mv and is over driving your phono preamp on the lowest gain setting, and see what they say.

Pivetta, I used the alligator clip clipped on the ground portion of the RCA jack. It was cumbersome and would work its way loose. But it did identify the problem. However if you have disconnected ed the Rt. Channel and the hum is there, this not the solution. 
Hard to say at this point, have you double checked the cart leads or tried another cartridge? There used to be an issue with Grado carts producing a hum as the tonearm approached the spindle. I remember reading that there were "Mu metal" shields to place around the motor, but really don't recall much beyond that.

I'm using a Rega Fono phono preamp and still have the hum issue. But I think it could be the cartridge. My RP3 came with a Elys and I had the same hum. Thought upgrading to the Exact might take care of it. Only have about 40 hours on the cartridge so hate to change but it my be the solution. 

" Only have about 40 hours on the cartridge so hate to change but it my be the solution. "

Phono carts go through a lot of break in. There were times when a new cart sounded so bad, I thought it was broken. 40 hours is a good start, but don't make a decision until you have at least 100.

Thanks Sfall. I understand where you are comig from, however I would not blame my dealer (at least not yet). He was very gracious to let me keep the table for about 10 days about month ago and I think that it was just a matter of a scenario in which I did not check the tonearm pushing it closer to the spindle. Again at moderate levels is not intrusive since I am using a 250 watt per channel Krell amp and I will never turn it up to the max level of 5:00 pm.  I also checked the wiring in the cartridge and it is absolutely correct. I am obviously dissapointed that the darn thing is doing this. Both my wife and I are professional musicians and absolutely love the way the table sounds and we find  it very musical. More so than my old Linn.  I am willing to take small steps and worst case scenario exchange it for something else. Will talk to my dealer on Tuesday since they are closed tomorrow. Thanks again for your input and happy listening.