QUOTE
Several members of the kX Forum (mentioned above) here on Driverheaven have mapped the AD_EXT header that appears on most Audigy 2 series cards. Creative caused uproar in the modding and sound enthusiast communities by not publishing this pinout as they did for the AUD_EXT that exists on the old Live! and Audigy 1 series cards.
However this has changed
However this has changed
http://www.bih.net.ba/~info.com/ad_ext.jpg
Source: http://www.driverheaven.net/showthread.php?threadid=51281