I found a number of sites where people posted their problems with Soundmax. I would suggest googling "Soundmax driver problems" and seeing if any of those help you out.
Have you downloaded the latest drivers from the Asus website?
If you don't get any help from those sites, here is a FAQ for Soundmax, which might offer some solutions:
http://forms.analog.com/Form_Pages/s...upportFAQ.html