I’d been chasing a hum/buz for about 3 years, and gave up on trying to find the root cause. Now during an equipment upgrade rewiring effort I’ve decided to try again and I may be getting closer to the problem but need fellow Outlaws to weigh in. (Gonk I hope you’re out there.) I guess it’s best to start with the setup: 990, 7500, Pioneer Elite DV-45A player/SACD/DVD-Audio (I think the culprit), Denon CD changer, Thorens turntable, Panamax line conditioner, and now a new Pioneer Elite Pro 111 Plasma Panel (not yet hooked up).

My cable service is Comcast without a set top box and for the current testing is disconnected at the wall. I am not using the 990 for video switching. The 45A connects with component video directly to the (former) Sony TV. (This is when I discovered that removing the component video connection, the speaker hum went away.)

All power runs through the Panamax except the 7500 which goes to a separate 20A dedicated circuit. The Panamax is on its own 15A dedicated circuit. Again - no cable lines tied in for the current testing. (Cable normally went into Panamax, then to old VCR then to TV.) The 45A is not a grounded plug (only 2 prongs). For the test, I’ve plugged the 45A into both the Panamax and to several completely different outlets, with no change in hum.

As stated above, the speaker hum disappeared when component video was removed between TV and 45A. I then tried connecting s-video between 45A and TV without the component video connected and got hum. So, any video from 45A to TV was a problem.

Now I began to focus on the audio between 45A and 990. The 45A connects to the 990 with 5.1 audio, digital audio and 2 channel audio. With either video lines (component or s-video) between 45A and TV in place, upon removing both the 2 channel audio and/or the digital audio between the 45A and the 990 – the hum GOES AWAY! The 5.1 audio connections from 45A to 990 doesn’t seem to be affected; i.e. they are still connected and the hum disappears with either the digital or 2 channel audio removed. (Are we getting closer??)

My question – what now? Seems the 45A audio section is a problem but short of ditching the unit do I have any other options? Oh, all cables are (do I dare say it) Monster brand so they’re not run-of–the-mill stuff. I am waiting for Oppo to release their new all-in-one HD player, but in the meantime do I look at maybe grounding the chassis of the 45A somehow and would that even do anything? Would love some fellow Outlaw thoughts and/or ideas.

Thanks a bunch.