Maybe an alternative would be to plug in a number of physical USB audio devices and then programmatically "unplug" and "replug" them: [Simulate USB unplug/replug][1]

Another alternative might be to have a number of bluetooth audio devices within range and programmatically connect/disconnect them: [Programmatically connect/disconnect bluetooth headset][2]


  [1]: http://stackoverflow.com/questions/5297304/how-to-simulate-a-usb-unplug-replug-after-the-device-is-safely-removed
  [2]: http://social.msdn.microsoft.com/Forums/en-NZ/windowspro-audiodevelopment/thread/0af0e34b-4628-4839-9222-2b56c1b4bbe3