Troubleshooting
Microsoft Answers
In 2010 Microsoft moved to new forum software.
Also new is the participation of the MS helpdesk.
They are very good in copy/pasting KB articles for you.
Hopefully the one they copy/paste is related to your question.
Microsoft answers - music and sound forum
Troubleshooter
If you have problems with the audio, a simple solution is to go to the control panel and run the Windows Troubleshooter.
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