Humming Help

I just hook up my CD player to my pre-amp and a loud humming sound appears with new RCA to XR cables. I need help (any suggestion would be apreciative). Here is the situation. I use a Proceed Pre-Amp with balance CD1 inputs. But the Pioneer Elite 45A CD player does not have balance outputs so I use RCA to XLR interconnects to go from the CD player to the Proceed pre-amp. This cause the loud humming. I then switch to CD2 on my proceed which only uses RCA inputs, and the humming goes away. So the proplem is within the RCA to XLR cables (brand new from Moon Audio). I really like to use the XLR inputs from the pre amp. Is there a way to fix this problem? I think it is a grounding loop problem. I did try to use the 2-prong AC adapters (the cheating method), the humming is less but still present. Please advice on getting rid of the humming noise. Thanks s much.
Musical fidelity A3CR
Proceed Pre
Pioneer Elite 45A
Silverline Sonatina II
Audioquest cables
No AC conditioners yet?????? Will this take away the humming?