While converting MKVs to WMV using 2 pass CBR, at 50% about half of the files I convert will receive an error and the program will crash.

I encode the WMV's with 5.1 surround sound, but I've been reading about what I believe to be the fact that Xpress can read but not output 5.1 sound, which seems silly. But that said, I can output 5.1 sound when I don't use the DirectShow reader to read the audio directly from the MKV, but use the MPEG reader to pick up my ac3 file.

I've deduced it enough to be audio-related. I used to import separate audio and video streams and didn't have the problem until I fixed the need for separate imports. I use AC3filter, and now whenever it gets to 50% it crashes. However, if I go back to my old ways and import the audio separately, it doesn't crash. I have a feeling it's gotta be something to do with my AC3 settings.

Any ideas?