Maybe This Will Help Someone Else

[Starise]

I picked up a very annoying hum in my studio interface. After spending hours crawling under my desk  re routing cords, checking grounds in my power panel, the hum was still there. I invested in a good power strip with EMI/RF interference protection. I had my interface pegged as the suspect and was ready to replace it until I remembered my cable company recently replaced the line running to my house. Initially I discounted this as a potential problem because my cable worked fine and all of the connections in the house were grounded to each other.

Just so happened that the cable tech called to see how it all went ( they subbed an outside contractor to install it underground). I mentioned the hum issue thinking the whole time it couldn't be the problem. The tech came by to check the work and found the earth ground coming into the house was not ran.He added the ground. Problem went away. I wasn't under the impression that cable lines were capable to transmit that much if not grounded.

So if you get a ground loop type of hum FYI don't eliminate this as a possibility.