How To Enable/Disable Volume Icon in System Tray
If you need to automate the process of enabling/disabling the sound/volume control icon in system tray on Windows XP, here's how you can do it easily.
Open the registry editor and navigate to the following key:
You should have a DWORD called Services. If Services value is set to 1F, the volume control will be visible in system tray. To make icon disappear, the value should be changed to 1B.
TIP: I've also noticed that if you set the Services DWORD key to value 1E, you will get the same result as for 1F. I'm not quite sure what is the difference between those two values as both give the same result.
You can make a registry key and publish it via Group Policy to distribute your setting across your domain.
Both registry keys are available for download below: