I searched for this topic and didn't find any suggestions specific to my need: I just added some KRK powered monitors to my system and am now having trouble with 60 cycle hum and obvious noise from my PC (the noise changes with screen changes from the computer). I'm running a very basic system with sound coming from the back of my computer's sound card, through a cheap mP3 extension cable (converted to RCA plug inputs), into a home stereo EQ, and into the monitors. I had some noise previously with my setup using an amplifier and Bose stereo speakers, but now it's significantly more pronounced. Troubleshooting so far: 1. the cables from the EQ to the speakers don't seem to be the culprit - no noise if I unplug the input from the computer to the EQ 2. Even though it sounds like it should be monitor related, when I turn off the monitor, I'm still getting exactly the same noise. My best guess is that I need some sort of shielded cable to run from my computer to the EQ. Any ideas?