Help with buzz / hum that's making me insane r

There are few amps that don't produce the hiss you describe if you are talking about getting your ear within six inches or less. The more efficient your speakers the more noticeable the hiss.
There are two amps which come to mind that were dead quiet, the Acurus A-200 and Sony TA-F707es. A noisy amp that comes to mind was the Portal Panache. It hummed and hissed and also produced an annoying thump during power on/off. The odd thing is the Portal was one of the best sounding amps I've owned once the music started.

The amp is dead silent. I just disconnected everything, save the amp and threw the breakers on the rest of the house and the hiss was still there. Then plugged in sources one by one, then added video section--still hiss. Then powered up rest of house--still hiss.

The hiss is only audible with ear next to speaker (the same was the case when I connected different speakers, so it's not the speaker, and the hiss was there with different amp, so it's not the amp).

I'm realizing I may be a big huge idiot. My wife feels, and she has very good ears, that this is just a more revealing system then any I've had, so voices actually have texture, as opposed to always sounding pristine. I can't imagine it's a ground loop, since I've disconnected everything and the sound is still there. The sound of my system is amazing, so maybe I'm trying to hear something that isn't there, which may be true because I don't notice it on all recordings. Can this hobby drive you crazy or what! If others can chime in as having experience this, or it being normal (as has happened in this thread) then maybe I need to trust that advice.

The hiss with your ear next to the dome tweeters means they are working. Agree with Herman it's not a malfunction. Advise you not increase the volume above normal listening levels to listen only to the hiss.

You can lift ground by adding a two prong cheater to the end of a three prong plug. So long as one component is properly grounded all the others linked via interconnects will share that ground. That's why if you did have hum, which sounds like you do not, the hum will persist even if the offending units are turned off but remain connected.

Dissatisfaction with the system's sound indeed indicates distortion. Surely it has nothing to do with your operating dome tweeters.

Enjoy that pretty room you have but move the carpet over so it's centralized equally between your speakers.

Thanks Rockvirgo, I am moving the carpet tomorrow. Can't believe I never picked up on it. I have been, and am still VERY happy with my system; however, in thinking about my hiss issue, I've decided there are two separate things going on:

1) The tweeter hiss is perfectly normal and only audible if ear is at tweeter
2) I could have a sibilance issue do to recabling and adding new ICs

Assuming the sibilance is cable related, I guess I'm wondering what to do. I didn't notice it before installing the Nordost cables, so I will swap them out and see if that is the issue, although I'd be surprised (wouldn't be the first time). If that's not it, I'm wondering what my next step should be. My speaker cables are 3 meters, which is more than I need, so I've got the excess length coiled under my stand. I had them this way before the sibilance became an issue, although I did recently remove them and put them back in, and I know purist cables are thought to take a while to settle back in, so maybe it's just a waiting game.

If it's not the SCs and not the ICs, then what next? From reading other descriptions of this sibilance issue from other people on the net who've experienced it, I'm pretty sure that's what's going on.

Should I clean my connectors? cap off any unused inputs on my integrated?

Fold the excess speaker cable concertina style (like an accordian) back and forth like a sine wave instead of round and round. Coiled wire behaves like an antenna or motor or something. Best of luck finding the sibilance.