Here is a heads up in the event that others encounter this.

I most recently got the Klipsch Promedia 5.1 speakers to use on my wife's computer with a SoundBlaster Audigy Platinum card. I followed the directions on what and where to hook up the wires and such, but I could not get the center speaker to work. I then did a speaker test and all of the speakers including the center sounded off. But no music, or sound of any kind would come through. I tired everything, new wires, made sure speaker itself would work you name it. I even took the speakers to my computer where I have a SoundBlaster Live Platinum 5.1 card in it and STILL no sound out of the center speaker.

I then contacted a person at Klipsch Promedia with this issue and here was her response..

This is actually a very common complaint with the Audigy card... I was unable to find a solution from Creative, but another customer sent me this
solution just the other day. Here's what he said:

"First minimize the playcenter to it's smaller size. The playcenter will then have a small tab on it on the right side. Open the tab to expose a keypad. At the bottom of the keypad are the letters CMMS. click on the CMMS and a screen will come on indicating whether the cmms is activated. Click on and the center channel will work perfectly. Hope this helps."

I tried this fix on my wifes computer and it worked. I also looked at my computer and Play Center had CMSS also enabled.

Creative still does not have any info on this issue and since it seems like they never will, I wanted to post this info for everyone. I talked with a tech at BestBuy regarding this issue, and he commented that a lot of customers have returned their soundcards due to an issue like this. Some have also returned speakers. Who knows, maybe when enough Audigy and Live cards get returned, maybe something will be done about it by Creative.

p.s. The Promedias ROCK!!