The Gamecom Commander is plug-and-play with both the dual 3.5mm connectors and the Dolby USB adapter, so no drivers are required for installation. If you've plugged in your headset and are not hearing any audio in the headset, check to make sure the headset is selected as your default audio device. To do so in Windows 7:
Click Start, and then Control Panel.
Click the Sound icon.
On both the Playback and Recording tabs, ensure the green check mark appears next to Gamecom Commander.