In addition to the above, if you are still having trouble with your audio, make sure your Windows Audio Services are turned on (Win XP).
Right click on My Computerand select Manage. From the computer management window, expand Services and Applications then click Services to open up the window listing all available services. The ones labeled 'started' are currently running, and the startup type 'automatic' denotes a service which is started by windows each time the operating system loads.
Find Windows Audio. Make sure it is marked automatic and started. If not, right click on the highlighted service and turn it on.
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