Magic Box by Mondial

Yes. I induced a cable hum when I had cable music dircted to my stereo system. This occurred both with the digital output as well as the RCA. So.. I bought a Mondial Magic Box and connected it. Hum is gone! I can't tell you what is in it as mine is riveted shut. I can only guess that it contains some sort of groung loop isolation circuit. I works very well and I can recommend it highly. It's a very easy and effective way to deal with cable induced ground hum. Happy Listening, McFarland

The Magic is the best one I have used. They offer a version with a built-in splitter but I found too much signal loss for my taste, I use the single version. Jensen also makes an inline gound isolation transformer.