For some time I've been trying to eliminate the hum through my audio system caused by my Tivo and DVD player. I tried the Xantech ground breaker 604 ground hum eliminator Byteme was selling, (see the thread):
http://www.audiocircle.com/index.php?topic=7417&highlight=hum+eliminator but it wasn't compatible with my Tivo Direct TV setup. When connected between the coax feed from the satelite and the Tivo, I had no hum, but no signal either. I've been looking for a line level transformer to eliminate the hum in the audio chain rather than through the Tivo's RF input.
I found the ART Clean Box II at Sweetwater, a professional audio outlet with an excellent reputation both on the internet and in the midwest of the U.S. The Clean Box II is a stereo transformer offered for $35.97 from Sweetwater with free shipping TO THE LOWER 48 STATES.
The unit is simple to connect, having two TRS (1/4 inch phone plug) inputs and two TRS connections for output. The inputs and outputs are clearly marked on the top of the box so it's a snap to connect with the proper audio cables or adaptors. I connected the box between my audio line-level switch box where my Tivo and DVD player are connected, and the long run of cables which feed my preamp's "Tuner" inputs. After connecting the unit, I cranked up the volume with no program input, and was very happy to hear that the annoying hum/buzz from the video components was completely gone. Only the low-level noise normally heard through my other preamp's line-level inputs was audible.
After listening to program material from the Tivo, and a DVD movie (Second Hand Lions), I can say that the audio through the Clean Box II is more than acceptable for these sources. I don't use my DVD for serious music listening, so I can't say whether the transformer introduces any problems in the audio signal passing through it. Since I have another source of ground loop hum in my system I'll probably give it a try when i identify the offending components, but the hum and buzz from the video sources was substantially louder than that from the general ground loop problem I have, hence my desire to eliminate it first.
I can say that for roughly $36, I've eliminated the hum from my video components and the audio i hear from these sources is more than good enough for enjoying a movie on DVD, or for watching Direct TV from my Tivo.
If RF hum elimination doesn't work in your system, and your not ready to part with the money to purchase a high-end transformer like those offered by Jensen, i'd recommend giving the ART Clean Box II a try. If you're reluctant to use adaptors to convert your RCA connectors to TRS plugs, you could either modify the Clean Box II to use RCA jacks, or get some cables already terminated in TRS plugs. ART may also offer the unit with other input types, at the price I didn't bother to check. Now that I know it works and the audio is decent, I'll look to see if other input connection options are available.
The URL for purchasing them from Sweetwater is:
http://www.sweetwater.com/store/detail/CleanBoxII/ART's web site is:
www.artproaudio.com