I just read the article and it refers to a coaxial cable between the SW and AV from what I understand. In my system and the ones I have built there never has been, it's just one cable with a canare connector. I have noticed a hum from my SW but only when playing Blu-rays on the PS3. The hum will go away if I turn the receiver to (Pure Audio) that's what Onkyo calls it anyway. From what I understand it turns off unnecessary "things" in the receiver. It's weird though I don't hear it through the Tivo or Apple TV only the PS3....Any ideas???
You have a ground loop. If you have an Axiom subwoofer, there is a ground screw you can remove on the back of the amp. There are chances that might be enough to stop the hum.
If not follow this guide to eliminating ground loops in your system. Here is a quick snippet from the article.
Start simple. Troubleshooting ground loops involves taking things in order and checking a few basic, common elements to see if the problem is simple, or complex. For example, if adjusting the volume on your processor/receiver does not alter the hum level, then the problem must be occurring after that point. It if occurred prior, then the receiver/processor would typically raise the overall level of noise. Make sense?
Work in the following methodical manner:
Start with the processor receiver to determine if the hum/buzz is source-related or due to a ground loop occurring after the amplification stage
Note any recent changes to the system that brought on this problem. Chances are, you can more easily isolate a problem if it just starting with the addition of a new piece of equipment.
What can you do quickly and easily to isolate or identify the problem and point to the proper solution (i.e. unplugging the cable from the wall to see if the Cable TV is the source of a ground loop.)
One other test to eliminate your receiver or processor is to see if the hum changes based on what input you have selected (DVD player, Cable TV, etc.) Does the hum change or go away when selecting a different input? No? Then your problem is occurring at a later stage in the system (most likely a ground loop caused by the addition of an amplifier or powered subwoofer with a 3-prong power cable.)
The final test is to unplug your Cable TV cable from the wall. Does the hum go away? It did in the case of Reference System 3. Eureka ! There must be a ground loop in the system involving the Cable TV line.http://www.audioholics.com/tweaks/connec...em-hum-and-buzz
