Radio Hum

I just hooked up a pair of conrad-johnson Premier 8A monoblocks to a c-j PV-11 preamp, and I have a wicked hum, even a zero volume, in only the right channel, and it is picking up a radio station. I have changed and moved speaker wires and interconnects to no avail, though it does get better and worse with movement. It will not happen in the other channel. What am I missing? What else should I check? Is something wrong with my preamp, cables, power supply???

Thanks, Brian.