Strange Intermittent Background Sound in Windows 7

Solution 1:

Okay, same problem here. I did fix it by clicking the Volume Control » Mixer » System Sounds icon to bring up the system sounds selection window.

Scroll down and look for "device failed to connect". Choose that. You will notice it's the same sound that's looping.

All I did was use the drop down menu and selected None. That stopped the repeating sound for me, for now. It may not be a fix but it works!

Solution 2:

Have you installed anything recently? Hardware or software?

What I would advise you do is open up Device Manager and just watch, if this is hardware, it should refresh and you should be able to tell what device was added or removed.