Ok. so getting hum when the TV is on. when i unplug the coax cable from my EP350 the hum goes away. or when i unplug my component connection from DVD player to tvthe hum goes away.
So 1st question. where's the ground screw on the EP350? unfortunately the manual online shows EP175 specs and i don't want to remove the wrong screw!
i should also mention. i have no cable, so ground loop not coming from cable outlet.

I don't think the ep350 has a ground screw, I think it is only the DSP based subs (500, 600 and 800)

The current EP350 doesn't have a ground screw.

I think you might need to look at where each component is plugged into the wall and try either the same outlet or different outlets and even resort to a very good surge supressor/power conditioner, some reports say they have helped ground loops.

tried all that short of the conditioner. it'd likely be cheaper for me to upgrade to a bluray player and get rid of the component connected dvd player i have right now than buying a conditioner...oh well

or at the very least the same price but the conditioners add that cool factor to the rack

My conditioner is a Monster brand. Yeah, I know, everyone likes Monster.

Many Monster products work well, it is just the price they charge that we have issues with.

Blackie, if you've already tried the simple(and cheap)stuff like plugging into different outlets, maybe some expense is necessary, but a "power conditioner" shouldn't be the answer. Since removing the input cable to the sub stopped the hum, cutting the ground loop at that point appears to be the answer. An audio frequency ground loop isolator such as this Xitel item installed between the receiver and sub should do the job.