This tweak prevents the system beeps from being audible without altering any other audio settings.
Registry Key: HKEY_CURRENT_USER\Control Panel\Sound
Modify/Create the Value Data Type(s) and Value Name(s) as detailed below.
Data Type: REG_SZ [String Value] // Value Name: Beeps
Setting for Value Data: [0 = Disabled / 1 = Enabled]
Exit Registry and Reboot