Hi, I have wanted to achieve this for ages, but have failed to find a program. I to have a Audigy2 ZS, I posted a thread a while back asking the same question as you, but no one could help me. My post: I have my Stereo TV Tuner plugged into my line-in, and I want to use ProLogic on the line-in signal to achieve 5.1 sound, because most of the programs and even most commercials have a Dolby Surround (Stereo) signal. note: CMSS etc, isnt true Dolby ProLogic, meaning it only adds reverb and delays etc, it dosnt properly "decode" the signal. Josh