It is in the Windows sound system settings. With the 7.1 USB sound device plugged in, look into your sound settings for speaker arrangement and make sure it is set to 7.1 (8 individual speakers). Also make sure the driver for the device is set for 8 channels of output. Then readjust the correction amp.
http://laserboy.org/forum/index.php?...sg6603#msg6603
James.