Hi. I have been using a Pro-ject Debut II tt and was hooking it to my Denon receiver with no problems. However, I decided to replace the tt with my old Rotel rp5300. Hooked it to the NAD stereo amp through a phono stage, and I am getting loud humming out of it now. The ground wire does not help at all, but the hum decreases (not totally eliminated) when I touch the tonearm... Any suggestions?