Loud hum in one channel

I just finished setting up an Empire 598 III turntable, and, unfortunately, am getting a fairly loud hum out of the left channel, which will happen on the right when I switch the leads. I am using a Sumiko Blue Point, and the ground wire is connected. Any help on solving this would be greatly appreciated!
sounds like a phone pre is the issue.
Sure sounds like the phono amp in the pre-amp is indeed the culprit. That would need to be checked out by a professional but I would sure start with that. If it was the pre amp itself you would probably be getting hum/noise out of any setting (CD, AUX, etc.). Let us know. Hope it isn't too expensive!!!
Thanks, guys. You know, I was never enamored with that phono preamp that was installed, and I wonder why it took the Empire TT to bring out all the bad in it, when the Funk was playing not too badly. At any rate, I will shop for an external phono pre-amp and try it that way. I hope that is all there is to it.