Thanks Prog, you're right. I downloaded ProgDVB 32 bit and can now select the AC3 filter under codecs and get audio.

Hey guys, I've run into the same issue. Already have AC3Filter installed. When I go to File>Properties in ProgDVB, I can see "Audio decoder AC3" under Filters.

When I go to Options>Audio>Codecs>AC3, I can only select from:

Microsoft DTV-DVD Audio Decoder
WMAudio Decoder DMO
WMSpeech Decoder DMO ...