Lets say, theoretically, that it does something to reduce the jitter on digital output, via some software that ensures the timing of the digital signal is as good as it can be. That logic would actually make some sense to me, as my DAC is less effected by sources with a lot of jitter, and, does not have the most ideal connection from my computer (optical to PC Link II to BNC coax), meaning that either the only small amount of improvement I hear is negated by one or the other.
This is entirely amateur speculation, of course.
This is entirely amateur speculation, of course.