I had the same problem once. I fixed a littel cheaper than the other guys. I converted the 75 ohm signal to 300 ohm then back to 75 ohm and the problem went away. You can get such devices at Radio Shack.
Cable tv induced power hum
I have a Proceed AVP HT processor connecting EAD Powermaster 2000 amp, CD,MSB Link DAC, DVD, VCR, Phono, FM, Subs, & Cable, power connected thru Monster HTS 2000. If I switch Amp direct to wall outlet I have a huge hum. Thru Monster powerconditoner it quites down, but is still present. If I disconnect cable from VCR or TV & it goes away and am left with slight speaker hiss. How can I remove hum from my system? Do I ground cable, and if so how? I have no converter box. I have @home internet connection thru cable. Should I try some technique with sources other than Cable TV lead? Should I get another power conditioner or another type power conditioner to eliminate the hum? Thanks in advance for any assistance you can give. Larry Norton