Need help finding unwanted background noises

This problem has existed for some time and is becoming a real annoyance.
I do not believe that it is associated with my computer speaker system because I can have them "off" and be using only my headphones and, in fact, that is when it is most annoying.

About three months ago, I purchased a nice set of earphones that I could plug into my desktop audio and listen to audio without bothering the boss (my wife).

It became evident, immediately upon headphone use, that I have background noise that is constant. There is a medium pitched beeping sound that has the frequency of a beep a second that is constant even when the system is sitting idle. Every operation that the system goes through initiates a corresponding, additional, unwanted background sound, including the cycling of the hard drives (I just installed a new (second HD), the mouse, left and right arrow keys on the keyboard, any every system process generates additional noise. The volume of this interference is "background" level meaning that it is similar to the background noise of one's car engine's RPM coming through you AM station audio in a car that has a radio resister issue.

I, of course, have numerous power cords that connect to a fairly good quality but, six year old power strip that the tower, printer, computer audio speakers and a table lamp.

I recently purchased a new laptop and purchased a logitech wireless mouse for it. I switched my hard-wired track-ball mouse with the wireless mouse and nothing changes.

I have windows XP on one drive and Windows 7 on the other and I get this unwanted noise with either system.

I haven't started to eliminate unnecessary cords that are plugged into my power strip, yet. I thought that I would throw this post up and see if anyone has ever experienced a similar annoyance and have been successful in isolating and eliminating it..
Any help would be appreciated.
My system specs are posted.
Thanks

 

If Tony's advise brings no joy, the old crossing of wires is often the problem, meaning as in your HIFI system you should not have any cables cross power cords.
Modern day quality cables though have almost eliminated this olden day problem.
Just a thought.
hawk22

 

Thanks for the reply. I will add, here, that I do have some electrical and electronic aptitude, having spent four years in radar equipment bench repair (although it was forty years ago).
I unplugged the tower power cord and plugged it directly into the wall.
I still have the noise.
I wonder if I should open the tower in look for a loose ground terminal, somewhere. This tower is old and has been plugged in and unplugged many times. I suppose it wouldn't hurt to check the inside of the case where the AC goes in.
I'll hope for some other input, as well. Maybe I'll take the tower to the neighbors house and connect it, over there. That could eliminate house wiring.

 

I connected the power cord to the wall outlet, eliminating the power strip...no help.
I also check the continuity at the immediate outlets and others in the house...problems are not evident.

 

Plugged the headphones into the laptop. No "interference noise" detected.
The noise that I hear when plugged into my tower is definitelynoise from that machine...hard drive whirring, mouse movements and a constant medium toned beeping at about one/ second. The head phones (Sennheiser HD202) are impressive and relatively inexpensive. Plugged them back into the tower and background- interference noise abounds.

 

Faulty Power Supply in the tower? What you could try is to take the PS out of the tower and outside and blow all the dust out of it. Could be some buildup of dust that may be damp and shorting across different things in the PS. Not enough to blow anything or burn. Then put it back in. That don't work, try another PS and see if that does the trick.

 

I'll give it a try and report back. I've never taken it out, before. I've and vac'd but, never "blown" the dust out. ...let you know. thanks

 

If you use compressed air, use a pencil (or similar) to hold/block the fan blades so you don't overspin the bearings.

 

Good tip, Doc. Thanks. I'll probably get to this Wednesday. Looking forward to wearing my earphones without annoyances.

 

Do you, or someone you know, have an old sound card that you could try?

 

Some Improvement

Somewhat improved but, far from eliminated...

I removed the Power Supply and removed the PS case as best I could without cutting the wiring ties and took it to a local garage that lent me the use of their air hose. The PS was VERY dusty, inside. I had high hopes of a cure. I waited an hour to allow any moisture in the garage's air supply to dry out, re-assembled the casing and re-installed the PS in the case.

My first impression after the "blow-out" and re-seating was that the background sounds diminished by about 70% but they still exist and I still hear the interference. I'm wondering if this may simply be the sensitivity of the ear phones. More accurately, I was say that the interference is reduced to 70-80% of what it was when I first posted this thread but far from eliminated.

As I am typing, here, I have my earphones on and I just heard a hard drive winding down to a stop. The beep-beep-beep incessantly continues and movement of the trackball causes additional noise. Even when I use the left and right arrow keys, I get an associated noise corresponding to each character space as it advances.

I thought that I came across a post, some time ago, about determining the source of unwanted noises but cannot locate it.

 

Unless you have 2 HD, it was not a HD you heard winding down. It has to be running for you to be typing here. Have you tried the Head Set on another PC to see if it is still noisy?

 

I DO have two internal hard drives AND an external, used for backups.

Yes, I have tried the headphones on my laptop and NO- the noise does not exist on the headphones when they are plugged into the laptop.

Also, I am going to approach the neighbor in an effort to borrow an older sound card (he's a big-time-gamer), if he has one, in an effort to eliminate that possibility.

 

keeping the thread alive, I now have a sound card to swap into my machine but, haven't the time yet.
I did remove my card and wiped it and the contacts clean with some cleaner. Then I re-installed it...same incessant noise. I'll try the other sound card, as soon as possible.

 

Hi papernpaste

something you could try without (/before) changing the sound card:

does the volume of the interfering sound change as you adjust the volume control (i.e. master volume)

...if altering the volume (even down as far as zero, or muting altogether) makes no difference to the level of interfering sound, then stop here, it's a hardware thing.

...if however (as I suspect) altering the volume control changes the level of the interfering sound in your headphones, then try this:

(using XP for convenience, as I have no Windows7)

- open the volume control (for playback);
- from the options menu, select Properties;
- under "Show the following controls" you need to tick everything you can tick!
(it's particularly important to show the controls for any front sockets, even if your case doesn't have the sockets fitted)
- while listening with the headphones, go along all the individual volume controls ticking their "Mute" boxes;
...does this give any clues?

my hunch is that you may well find the interfering sound is being introduced through a particular channel (if you are lucky it may even may turn out to be a channel that you don't need to use).

Sound (wanted or unwanted) comes through these channels even when their controls are hidden...

best wishes, HJ (+ HD25s )

 

The used sound card that I attempted to swap turned out to be bad. (It didn't work at all). I followed Hugh's suggestions (Thank you, Hugh!), going to Volume Properties and "unselecting" virtually every option (the Master Volume must, of course, be selected in order to close the window)while headphones were plugged into various output jacks on the front and back of the tower. No change-the background noise still exists. When I increase the volume there is only a "slight" increase or decrease in the volume of the background noise. But, the background noise persists, even when the "one-and-only-selected" Master volume is Muted and all other boxes in the Properties Panel are "unselected. "