Weird noise when using headphone?

I recently bought a new computer, and whenever I use my headphones, I get this background slightly sharp continuous jittery noise. I don't have speakers to test if the same thing happens with them.

If I mute the CD player sound using the Volume Control, it disappears.

The sound also disappears when the CD-rom is being used.

Any suggestions on how to get rid of this sound?

i had the same problem but all i had to do was move my uv cathode away from my sound card. not sure if you have that though...