How can I programatically change the default audio device on a vista / win 7 system? Using C# or a Win API call?
John Gietzen
The WinMM API should provide the functionality that you request.
You would use the DRVM_MAPPER_PREFERRED_SET message, which is sent with waveOutMessage() function.
Documentation: http://msdn.microsoft.com/en-us/library/aa909789.aspx
However, if you are trying to send the waveform sound out yourself, you should look at the WinMM.Net library.
来源：https://stackoverflow.com/questions/1555156/c-sharp-how-to-programatically-change-the-playback-device