Noise heard when moving windows

Hi guys,
 
This is driving me nuts!
 
There is a low buzzing sound when performing the follow actions:
1) moving the windows around on the desktop by holding on to the left mouse button
2) moving windows with keyboard using the Alt-Space > Move
3) scrolling down pages using the mouse wheel
4) short buzz when opening and closing any application
5) short buzz when desktop changes wallpaper (best of Bing)
 
I can only hear the buzzing sounds when using headphones and the volume remains at the same level no matter what volume level I set. The strangest thing is that the buzzes can also be heard even when I mute the master volume. The buzzes sound like pulling of zippers. I have muted all recording devices by the way.
 
No noise was heard on my speakers when I unplugged my headphones, even when the volume was set at maximum. There is a function which allows me to switch between speakers and headphones when both are plugged in. When I set it to speaker mode, nomally the headphones will be muted but the buzz was still audible while normal sounds were heard from the speakers. This leads me to think that the problem was probably caused by the headphones jack but it doesn't make any sense as to why the buzz only happens when there are activity on the monitor screen.
 
My PC is running on dual boot (Win7 and Vista), same problem on both OSes. I already did some searches and tried several things like muting CD Audio but none worked. I have tested using different headphones on the same computer and all can be heard. There was no noise when I used the same headphones on my laptop. I had also tested using Audacity to record on stereo mix to see if the noise can be recorded but thank goodness, it wasn't captured.
 
I have heard people saying that this could be due to video card but I have no idea how to solve this and all the drivers are the latest versions. Ok, my sound card is the onboard Realtek card, I don't know if changing it to an external USB (EMU0404 USB) one will help or not.
 
Does this noise affect the quality of your recordings?

^This^

Also make sure the cables running all around from your desk to the computer are neat and organized. Keep Power and Audio cables separate. Sometimes all it takes are two cables intertwined that will make those noises.