Very slight "Hiss"

When I press my ear next to the tweeter, either channel or input selection, I hear a "hiss". I have tried chokes, and changed physical position of IC's. However, I noticed that if I select an input that has nothing connected to it, the hiss increases. The hiss is small, but it really bugs me all the same. Might there be a way to eliminate it??
Quit pressing you ear next to the tweeter!!!
It is most likely coming from the pre-amp, since it changes with input selection. Some components are quieter than others. I have experienced it through the years with differnt components. Nothing I tried helped. e.g. ground changes, cable routing, component placement, etc. I know it bugs you but I think you are opening a can of worms that could ultimately cost you your sanity. Luckily I gave up before I got to the point..hee hee ha ha ho ho their coming to take me away ha ha:)
What preamp are you using?
I get the message - OCD!! I mean, my sweet-spot is 15' away, I cant hear the hiss there, but I was wondering if it should be silent. The source component is a Krell KAV 400xi.

I bet if you stand on your head for an hour you'll get a headache too, but why would you ever do that?

In normal use why would you ever press your ear next to the tweeter?

I agree with Tpreaves

The 'very slight hiss' you hear means you are still alive. I know of NO audio electronics that give ZERO hiss. Some may become really inaudible, but trust me, it is still there, just below your threshold of hearing.
The noise is just the stuff of electronics. Some are worse.. when you can hear it from your seated position THEN start to do something about it (which basically means throw money at it).
Elizabeth is correct. No electronics can achieve zero noise. What you guys are hearing is residual thermal hiss, which occurs in all electronics, regardless of quality or price. As long as hiss is inaudible from the listening position on the quietest music passages, there is no problem.

Tweeters have a slight hissing sound at "Ear-to-Tweeter" distances when the amp is powered up. This is normal. If you other drivers are "humming" this is differant and is likely a ground problem.
Very common in various audio products.
Thanks to those who explained the nature of electronics and the fact that what I observed regarding "hiss" is normal.

Every electronics device (audio) they produce a normal hiss if you hear it very close. Dont find faults in your system when is not neccesary.
Thank you Chatta. From a normal listening distance as opposed to pressing my ear right up to the speaker the hiss is completely inaudible. I was holding my ear about an inch from the tweeter and only at this distance could I hear hiss. There is no problem with my system, this observation was a curiosity more than anything else. I've moved on to just enjoying the music at a realistic distance.