Level Editor (annoying sound) background problem

[HumiliatioN]

So you say even though your speakers are off, and headphones unplugged, you hear this beeping noise?

I mean when my speakers are on I can here it silently sometimes, when I plug my headset I can hear it immediately and my friend only hears when I move my mouse and do something inside the editor. Really odd problem.

Can't still solve it, it's really bugging me.