Samsung SP2203XWCX-ZA - Manual (Page 30)

2-11 Installation and Connection
In Classic View of Windows XP : Go to Control Panel - [Sound and Audio Devices], and select the <Audio> tab.
On Windows 7 : Go to Control Panel - [Sound], and select the <Playback> tab.
2. Specify the default device for sound playback:
You can select the PC speakers or projector speaker.
The aforementioned information may slightly differ from some PCs or versions of Windows.