I am having trouble turning up the sound on my AVI files because the audio is encoded with ac3. Googling told me to open up the ac3filter config to adjust the sound, it doesn't open any program. I found the ac3filter.cpl which is supposed to open with the control panel but when I double click on it, nothing happens. I've also tried running it as Admin. I did a system restore. I'm not sure why this CPL file is not opening with control panel like it says it's supposed to. Any ideas?