HELP: How to get rid of AC hums and video noise

Hello Audiogoners,

I need help from members of Audiogon more experienced than I am with AC HUMMMMMMMS!!!

My video system is pretty standard: a SACD/CD/DVD player, an audio/video processor, a 5-channel amplifier, 5 speakers and a self-powered subwoofer. Plus of course the various power conditioners & transformers. Oh, I forgot. there are also the VCR, cable box, S-video enhancers and all kinds of wall warts associated with them. Well, maybe the darn thing is not that simple but I still think it is a pretty typical video system.

Anyway, each time I made anything that amounts to more than a minor change in this video system, I have to spend a lot of time chasing down those AC gremlins such as hums in the speakers and/or dark bars moving across the TV screen. Floating and reversing polarity of various AC plugs in even such a standard video system can be very time-consuming and frustrating--i.e. not always successful.

Is there a systematic method to chase down or prevent those AC gremlins?

Or is there perhaps a hum eliminator(like the Ebtech for music equipment) made for RCA connectors?

Any help to alleviate this frustrating experience would be greatly appreciated. THANKS.