beep-beeping sound.

I saw your post again now and I have some ideas. Sorry for the late reply.

It sounds to me like it's something operating in the system. Many computers have things like that going on, although it may not be a "beep" (often just static). It could be feedback from anything in the computer, probably not intentional (although I'm not sure... maybe it is for monitoring if the hard drive is going... that sounds odd to me though).

So, the first thing I'd tell you to check is to insert some headphones. Is this through the computer box itself or external speakers? Try switching that also (eg, no external speakers, or adding some) to see how that works. Then check which conditions make the sound. If there's always a sound, then it's going through your sound card. If there's only a sound when, for example, there are no audio devices attached, then it's probably something local in the box. And also be sure to check where the sound is actually coming from-- try headphones and see if you can hear it in the headphones or on the computer, because that's probably the easiest way to hear the difference.

Anyway, beyond that I'm not sure what to do, but at least you'll have some idea about how the sound is being distributed, and that could give you some ideas about how to fix it.

If it is just an internal sound and you don't often use the internal speakers, one option (somewhat destructive) would be to disable (unplug?) the internal speaker.
If it's going through the sound card, then you'll need to find the source. If it is a component of the computer, maybe you could get someone who really knows what they're doing to cut one of the wires, if that is where it's coming from-- but if it's going through one of the wires that connects something that is necessary, then there may be nothing you can do about it.

In short, check what kind of sound output generates the sound, then that will help you troubleshoot and maybe also to tell the manufacturer about a bug and get some help from them.