Consider the following scenario:

• You upgrade a computer to Windows Vista.
• The computer uses a SigmaTel HD audio driver.

In this scenario, audio playback no longer works on the computer. Additionally, you receive the following message when you position the pointer over the speaker icon in the notification area:

No output audio device is installed.

This problem occurs even if all the audio cables are connected correctly, and the sound driver appears to be working correctly in Device Manager.

Note: The notification area is located at the far right of the taskbar.