I am using a Sound Blaster X-Fi Notebook sound card connected to my JVC 5.1 audio receiver via optical cable. The problem is that ffdshow has trouble outputting anything above a stereo signal to it. The only real success I've had is using AC3 Filter v1.46. I took the advice of Creative's technical support in that they said it can only output surround sound through S/PDIF is if it's PCM. So, with AC3 Filter I used the "Output S/PDIF as PCM" option , but after experimentation the sound turned into clicking noises only for AC3 audio. I went back to default AC3 Filter settings and only change I made as I enabled S/PDIF. This would only work if I enabled it only after I started a movie otherwise I would get no sound or clicking. Is it possible to do this with ffdshow except without the bothersome enabling after playback? I've tried different configurations within ffdshow audio but I either only get stereo sound or Media Player Classic can't find any AC3 codecs, with ffdshow installed. This happens when I try to change to LPCM output or S/PDIF for AC3 and DTS.

Edit: When I open a video with surround sound, it only outputs stereo. If I enable "Force sound card to reint after seek / pause" in AC3 Filter the sound changes to full AC3. But just like the warning says for this option, it goes a little out of sync. I no longer use "Output S/PDIF as PCM" since there doesn't seem to be any effects with it disabled.