Karen, assuming you have both the Soundblaster Audigy and another sound card that works with Microstudio, I'm wondering about a possible fix, and your willingness to try something out.
With Audigy fully installed, try going into control panel, then multimedia, and audio.There are two blocks, recording and playback. it should be possible to select your old sound card there, effectively "turning off" Audigy.
Microstudio may work then. If it does, then it's possible that all one would have to do is turn Audigy on and off as needed.
I've doped this out with another audio capture device I have and it works. Prior to figuring this out I was having problems with this other device active when I tried to play Microstudio, and my problem got solved. Keeping my fingers crossed that this may also address the Audigy problem for all concerned, as it appears to be a similar situation.
Take care,
George
