I have a 25 foot component, and 25 foot RCA audio running from my PC to my TV. I have a cable modem connected to a "tap" output and then a ~30 foot coax running from the "out" port of the tap to my STB. The cables are all running next to each other along the ground. I noticed that the coax is causing a humming noise, and wavy video on the TV when I select the component input. If i disconnect either end of the coax, the humming and noise goes away. Does that mean the coax is not properly shielded, or perhaps the component or RCA? Is there anything I can do?