Faint speaker hiss

Was wondering if anyone here might be able to help me out. I recently acquired a new naim integrated (XS2) to pair with my Harbeth p3esr. I am using straightwire speaker cables which I've had for years. I noticed when I plugged everything in that the speakers have the ever so slightest hiss coming from them. I cannot hear it unless I get extremely close to to tweeter and te sound becomes non-existent once music starts playing. I have had the amp for about a week now and have kept it on 24/7. Does anyone know where the small hiss could be coming from? I tried different speaker cables/power cord and that didn't change anything. I also tried unplugging all my sources and left just the amp and speakers plugged in ad still had the faint hiss. Like I said, it's not audible unless I really get my ear close to the tweeter (about 3 inches). I might be nit picking but was wondering if anyone has had experience like this before? Should I try a different outlet? I am in an apartment so only have one or two places to put everything. Any help would be greatly appreciated. Thanks!
If you have to be literally inches from the speaker to hear it, what's the problem? I get the same thing through my F5 and there's plenty of commercially built amps that are louder than that. I do get a bit of a 60Hz hum that you also need to be inches away to hear which may be due to sub-ideal grounding topology, but you can't hear it 10 feet away so I don't really care. 
Don't lose sleep. This is normal and very common. It's the noise floor of your amp and no power conditioner or magic power cable will alleviate it. Anyone who tells you otherwise is completely full of ****
No this is not normal anymore. I just checked with my own P3ESRs (driven by an old refurbished Quad 405-2 and just a volume control): nothing, absolutely nothing, no mains hum and no noise. It might be different if you are a young girl, of course, since they have better high frequency hearing (I will have to ask my daughter). With very efficient speakers you might just hear something, but not with inefficient ones like these.
Cables do not make any difference in this respect, so they are also out. And since you also hear it when you have disconnected your sources, it is not those either.
So it is the amplifier in one way or another. Do you hear it on every input or only on some?
If you only hear it with your ears 3 inches from the tweeter, don’t worry about it. I hear a slight hiss from my phono preamp ( tube ). If you don't hear anything from your listening position why bother with it?
Have 110db 1 watt loudspeakers running and no noise so while a bit of hiss can be normal in some systems its possible to not have any. Many point to tube amps as having noise but I have found that some SS amplifiers can be even more so.
You shouldn't worry about it given your current speakers but keep this in mind if/when you decide to upgrade or switch to more efficient speakers, e.g., > 92 dB/w/m, etc., since the hissing sound could become more audible. Ideally, the tweeters should be dead quiet if your amplifier/preamplifier - in case of separates, have a properly matched gains but there's nothing you can do with an integrated unit. One could argue this is an indication of a suboptimal design by the manufacturer.
No this is not normal anymore.
This statement is incorrect. With nearly any integrated amplifier a hiss will be heard on that speaker. But it is of no consequence as others have pointed out; I've yet to meet any audiophile that listened to their speakers from only a couple of inches.
This.  All brands and models of amplifiers vary, as will individual examples of each.  Above all, don't go crazy throwing $$$ at this problem because you'll never eliminate it.  The most quiet integrated I've ever heard is the Ayre AX-7, probably because of built-in filtering and the unusual design/configuration of its transformer.
I asked my young son: he hears a faint hiss at very close range.
They almost all do. I never had a speaker/system that was completely silent. But Can't hear a thing if my ear is few inches away. 
While as others have stated the "hiss" is normal, there is something to keep in mind/try. The hiss should only get so "audible" and then cranking the volume further clockwise should NOT increase the volume of the hiss. Usually the volume of the hiss maxes out around the 12 O’clock position. If the hiss continues to get louder as you crank the volume I’m pretty sure this would not be considered normal.

Something else to try. RCA shorting plugs on the unused inputs of the amp. Can’t hurt and could help.

And yet something else.... gee I've learned so much from this forum over the years :).... the efficiency of your speakers do play a role. The more efficient they are, the more hiss you will (or could) hear.
Sorry for a late response but I appreciate all the feedback! I thought I should mention too based off some responses that no, the hiss does not get worse with more volume. It is a minor constant sound that goes away once music is played. The speakers I have are inefficient to say the least (83 db)  I did do a quick a/b with an old pair of paradigms that are around 90 db and yea the hiss was more audible but still nothing dramatic. As others have stated, it really shouldn't be a worry as it is so minor but this is a lot of money for me and I just wanted to make sure there wasn't a stupid mistake on my part that could have been causing it. Thank you all so much for the feedback 
It is a minor constant sound that goes away once music is played.

You're welcome. Note, however, that the hiss doesn't "go away". It's simply masked by the relatively much louder music. Hence the hiss is simply one component of your systems overall "noise floor".
Hi mgreg42.
This is great question that I also want to learn answers..
1-Try unplug all rca inputs(source or preamp isn’t connected) & Short your rca inputs of your amplifier.
If you hear a noise from your speakers it should be the noise floor(SNR=signal to noise ratio) of your amplifier..
I do not know unshielded speaker magnets can cause a hiss or not..
2-Try to play an empty(no music in it) flac or cd file from your system.You can find the file on internet.(google it).I also have the file in my computer.If you can’t find I can send it to you.
You said noise is gone when music is starts.Check the 2nd it really diseappers or not.

If when music starts noise is gone it is probably normal.Because when nothing is playing some source equipments shorts its outputs automatically any possible noise can get pass to amp is eliminated automatically.
Even output shorted some noise can leak to your amp..

There are some amplifiers with fancy S/N
like the benchmark ahb2 like 132db.

Reall issue here we don’t listen speakers like sea shell but we want to be SURE the hiss noise is really normal or not..
This is my first post in here..
Speakers themselves do not make any noise. You did not mention what source/input you were using. The phono input is always noisier than the line input as it needs more amplification.
I looked at the manual of this naim amp:
"3.4 Radio Interference
In some circumstances, depending on where you live
and the earthing arrangements in your home, you may
experience radio frequency interference. Controls on
broadcasting in some territories allow very high levels of
radio frequency radiation and both the choice and exact
siting of equipment may be critical. Susceptibility to radio
frequency interference is related to the wide internal
bandwidth necessary for high sound quality. A radio
frequency filter kit is available for some Naim equipment but
sound quality will be progressively compromised as more
elements of the kit are fitted."
Maybe this can also help?
Isn't this more common with tube amps???
The slight hiss you hear is normal its the noise generated by current flow through semi conductors and resistors in your amplifier.   

Good Listening

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Absolute silence when no signal is present is a laudable goal, but not an absolutely necessary goal. I have not found a direct correlation between system performance and the presence or absence of a faint hiss emanating from speakers. The presence of the hiss is directly influenced by the amp/speaker combination; i.e. take the identical rig and remove a higher efficiency speaker, and put in a less efficient speaker and the hiss diminishes substantially. 

When I was younger and newer to audiophilia this was an IMPORTANT thing to me. Now, with a more seasoned perspective it is relatively unimportant (Note clearly that I am NOT saying noise in general, especially noise is perceived to impugn the sound quality, is unimportant). 

If you have to put your ear to it, it's not a serious issue, imo. This is very common. Many audiophiles with hearing loss or noisier rooms have this and don't even realize it. I suspect the description that the noise is gone when the music starts is not true. (I'm NOT suggesting someone is a liar or foolish) I believe it is due to the presence of the signal noise and music that the very faint hiss is hidden. Even in silent passages of music such a his is exceptionally difficult to isolate. If there is a perception that the hiss is gone when playing music, that is your answer; it's not a deal breaker. 

selman, I hesitate to give an example mentioning actual components, though I have built hundreds of discrete rigs and encounter this regularly. I will not mention actual components because there is a form of delirium in Audiophilia wherein people react reflexively to anything perceived as potentially negative. I'll not subject perfectly fine manufacturers to such ignorant reactions. 

Simply trust what you are told about it not being a major issue, and that it can occur in many, many situations. If you hate it and must have absolute silence, change your components. It's that simple. BTW, I may be wrong on this, but unless the noise oscillates it would not be radio frequency noise. I suspect that would be very unlikely.  :) 

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