Well, here's a new problem which I'm having on my PC since about a month:

My speakers are giving that low and very disturbing sound to my ears. That's about to make a hole inside them.

I changed the speakers for no avail.
Tested the connection..
Restored my PC by using the "Restoration CD"..
No change.  

I thought at first that it might be a programs conflict or some adds or virus !!!   Well,   nothing of that.

That sound starts as soon as I switch my computer on. Yes!  even before "Windows" starts.

It's similar to the sound of a "true mouse" (the animal).  (No hidden mouse though      ).   But it's much more disturbing to the ears.  It's like a "SAW" sawing in the head.

Sometimes, I hear it without doing anything. But some other times I hear it clearly when I move the mouse (the side bar).

If I increase the sound volume I hear some more other disturbing noises accompanying it. Like the sound of the fire burning the wood or the grass.

Any idea?

Thanks...

Thanks Simon for the answer.

Well, in fact I thought of speakers connection to the sound card. They are well plugged. And to be more sure, I unplugged them completely and plugged other speakers which I have. It's the same result though.    

Well, maybe sound-Card problem or mother-Board. But I can listen to some more suggestions.

I don't like immediately to open the tower now (the case). it's full of plugged cables (on and around). Even if I do open it, I don't think I'll be able to see the problem by my simple eye. But I'll do that in case no other idea is there.

Any more idea will be welcome.

Thanks....

well, maybe you're right Simon. But if my memory is ggod enough, I think that my sound-card is integrated in the mother-board.

To be more sure, I'm going to have a look.

Well Simon, as I said, my memory seems good enough in this domain. My Sound-Card is integrated in the mother-Board. But anyway, I tried to clean the plugging place. It's the same.

Sandra, I did according to your suggestion and restarted the computer. Unfortunately, nothing changed.  Thanks a lot.

Any more thoughts ?

Thanks...

It sounds like you are getting electrical interfereence of some kind Youdi.

Have you added any new hardware to your PC recently?

Do you have a mobile telephone or DECT telephone basestation near your PC?

Hmmm, too much Star Wars I view, Yes

Apologies Joudi. It is still a bit early for me due to last night's

Just remove it and see if it clears the problem Joudi  
If it does then we know what we are looking at and can see if we can find a solution such as moving it to the farthest away slot on your mobo from the sound chip or maybe moving any internal wires that connect to the card, if there are any  

How strange.  It definitely sounds like electrical interference of some sort.  Is there anything else nearby, that could be causing it?  A cordless phone, or a mobile?  The only other thing I can think of to suggest is trying another set of speakers, if you have some, or could borrow some.