Description: The demo simulates an USB Desktop Speaker with Microphone which actually does not "speak out" but loop back the sound as microphone input. When an Xplained board running this program connected to a host (PC for example), with USB cable, the Xplained board appears as a desktop speaker for the host. Then the host can play sound through host software. The audio stream from the host is then sent to the Xplained board. At the same time, the audio stream received is also sent back to host from Xplained board for recording.