Do this on your client machine to get rid of the annoying beeps:

If you want to disable beeping sounds in Vista/XP/2003/2000 follow any one of the method.These commands assume administrative rights on the PC.Works especially well to hush Terminal Services Beeping.

Method 1

From Local Machine

To disable the PC Speaker beep temporarily from the command line type the following

net stop beep

To disable the PC Speaker beep for good run the following command

sc config beep start= disabled

if you want to disable beeps to go away even after a reboot, run the following commands

net stop beep

sc config beep start= disabled.

The space between start= and disabled is required.

Method 2

From Remote Machine

If you want to disable beeping sounds from remote machine run the following commands

sc remoteMachine stop beep

sc remoteMachine config beep start= disabled

Method 3

For windows XP/2000/2003 Users

Right click on My computer->Properties->Hardware->Device Manager->View -> Show Hidden Devices -> Non Plug and Play -> Beep -> Right click and select Disable

Now you need to reboot your system

Method 4

Using Tweak UI

Open TweakUI and click on General–>Uncheck the Beep on Errors and click on ok

http://www.windowsreference.com/windows-xp/disable-beeping-sound-in-vistaxp20032000/

by Stian Kirkeberg [Via]