Hello Sean
I assume you mean the speaker icon is missing form the lower right of the taskbar.
Click Start, Control Panel, (Settings, and Control Panel if in Classic Mode) and then double click Sounds and Audio Devices, then on the Volume Tab make sure the Place Speaker icon in the Taskbar is checked and click Apply. (If it is already checked then uncheck it, Apply, recheck the box and click Apply again)
If you wish to access the Mixer from the Sounds and Audio Window just click advanced.
Hope this helps

Bill