Signs of poor electricity in home...?


Ok folks I know pretty much that all homes have crappy power for electronic gear. However my dilemna is that I have continued to have a buzz type sound come from my spkrs whenever amp is powered on. This is the same case with three different amps and a recvr. I just completely disconnected everything and have all the gear everywhere in the living room. This was no small task.
Nht Controller
Nht Power 5
Nht Power 2
Oppo 83
Toshi HDDvd
AudioControl Bijou EQ
Panamax 5500ex
Nht A1 x 2 for bi-amping mains.
Nht X2

I use Signal pwr cables and my own custom made.
Signal, Bluejeans, monster ic's
PS Audio powerport

I have eliminated any cable combo as the culprit and have it narrowed down to the fact that with an amp plugged in, powered on, and just spkr cable connected to a spkr I get this slight buzz/hiss type noise. I mean nothing connectected to amp but what I said...electricity...and spkr cable direct to spkr. It is not the hmmmmmmmm of 60hz...it's a hiss like white noise makes when a tv channel would sign off-air if you are old enough to know what I mean. Anywho...it's bugging me to pieces. I have went to the breaker box in garage and eliminated it being the fridge in neighboring room, etc. Even with the Panamax it still gets noise to the spkrs mid/twtr...mainly mid. Volume has little or no effect on it if you are wondering.

So????? Dirty house power and what do I do. Would having a seperate/dedicated line help? I don't have dimmer lamps or any other of the typical buggers in the ac chain. No tv either as I have a Pj setup which plugs in where I use to have a ceiling fan and installed box/receptacle to pwr it.

I don't hear it if source is playing but sitting idle all 5 spkrs doing this is annoying. Suggestions please.
mnnc
I wonder if there is something you overlooked like an outdoor security light,etc.Try turning off all of the breakers except the one its on,and see if it changes.Another thing to try is a 50-100 foot extension cord,and try the system on outlets in different rooms.This should get you on the other phase leg powering your home,plus a different circuit.A bad breaker,loose connection in the breaker box could cause this too.Also,where your service ties to the feed/drop wire to your home,and the transformer(utility) could have a bad connection somewhere.
I had a weird similar problem (buzzing noise inside amp, everything else in house aok) that was fixed by tightening all connections in my breaker box. The manufacturer suggested that it was more than likely a neutral connection that was causing the problem.
Would be interesting to play with wrapping the receiver in aluminum foil to see if this had any effect on noise just to eliminate emi as a possible source.
Another thing is to carefully eliminate the ground connection (assuming there is one) to the receiver using a cheater plug.
Yet another thing is to plug in a high wattage light to the same outlet your receiver is plugged into & see if this changes the noise.
I liked the previous posters ideas also.
Hifihvn...interesting ideas. I will try some of your sugg...however, the loose connections in brkr box...forget it unless I kill pwr from outside main and then what do I tighten? When I look inside brkr box all I see is brkrs sticking out and ON or OFF. Where are the connection screws? Our pwr feeds are underground type. I could call pwr provider and have them do a chk/service if it's at no charge to me...pardon the pun. Thanks.

JJones...what would foil do or more important what would it prove? Again, excuse my ignorance, what would the plugging lamp into same plug/receptacle prove? What am I looking for during experiment/troubleshooting? Thank you too.
This may sound odd but I had this problem before.
I had AC riding on the ground. Try using one of
those cheater plugs. Three prongs to two prongs.
If you plug in the power cord into the cheater
plug and the problem goes away you can then look
into the grounding issue. It only takes a couple
minutes to try and costs nothing. Good luck
So a 'cheater' plug is one of those adaptors that has 3 female/2 male...? Basically eliminating use of the gnd pin being plugged in? Will this not hurt my gear? Not all the amps/recvr I have are being used at same time and a couple of them differ in design concerning having 2 prongs in their iec or 3 prongs. This is by the nature of the manufacturers design. All gear is US 120v.