Remove the Speaker Icon from the Tray

The speaker icon in the lower-right of your toolbar (Tray), enables you to open the Volume Control by clicking on it. To remove the icon:
1. Right-click the speaker icon and choose Adjust Audio Properties from the menu
2. At the bottom of the Audio Properties window, there's a check-box Show volume control on the taskbar, removing the check-mark in the box will remove the Icon from the Tray.
Now if you ever want to restore the Speaker icon in your Tray, you have to:
1. Click Start, Select Settings > Control Panel
2. Open Multimedia, and place the check-mark back in the Show volume control on the taskbar box (on the Audiotab)