2600 games look & sound crystal clear on my 7800 but 7800 games have audio and visual problems

[treismac]

I just bought both a ferrite bead and a gold A/V cord to root out rf interference from my new 7800. The result is that my 2600 games look amazing on my 7800, however when I play an actual 7800 game the system randomly emits a sustained audio buzz and the picture blurs every so slightly. What the heck? Obviously this goes beyond cable A/V cable problems and external rf interference. Is this a common or universal problem? Is this likely a "fixable" problem? Would an A/V mod rate of success be a toss up at best or a sure fire success or failure?

I am, however, very pleased with how great my 2600 games sound and look.

EDIT:

Hmmm... 2600 games still receive interference, just not as much as their 7800 counterpart.