Hi,
· When exactly do you get this background sounds?
· Do you hear the sound after closing all the programs in Windows?
· Does the sound come from internal speaker or external speakers?
Step 1:
I would suggest you to check Task Manger and see if any program is running on the background.
Open Task Manager by right-clicking the taskbar and then clicking Task Manager.
http://windows.microsoft.com/en-US/windows-vista/What-is-Task-Manager
Identify the process associated with a program
http://windows.microsoft.com/en-US/windows-vista/Identify-the-process-associated-with-a-program
Step 2:
If you are facing this issue while using internet explorer then first check if any advertisement program is running in the internet explorer Window. I would suggest you to perform Clean Boot on the computer and check if any third party program is causing the issue.
How to troubleshoot a problem by performing a clean boot in Windows Vista and Windows 7
**http://support.microsoft.com/kb/929135**
Disclaimer: After you used the clean boot to resolve your problem follow Step 7 to reset the computer to start as usual.
Also refer:
Adjust the sound level on your computer
http://windows.microsoft.com/en-US/windows7/Adjust-the-sound-level-on-your-computer
Tips for fixing common sound problems
http://windows.microsoft.com/en-US/windows-vista/Tips-for-fixing-common-sound-problems