Sounds like a RFI or EMI (radio frequency interference) problem.
One way to combat this is to hook up all your gear into a conditioned power source other than the conventional consumer power strip which I see a lot of katz using.
Before I invested in conditioned rack mounted pwr conditioners, I too would experience radio transmission through my setup.
Then I read up that I would have to connect all my gear to powered conditioners that specifically specialized in getting rid of this.
From that point on, I invested in at least five (8-10 outlet type) rack mounted (ETA & Furman) pwr conditioners as well as a APC battery backup unit to rid my system of any & all RFI issues (and it's been like this for at least the past 15+ years on the rack conditioners).
Though I'm not saying not to use consumer pwr strips, at least if you do, make sure they're branched off of one of the outlets coming from a dedicated conditioned pwr source.
And the way I look at it is...if the pros do it, why can't I.
But there's def plenty of info on dealing with system interference & hum.
http://www.etasys.comhttp://www.furmansound.com