I installed LAV splitter +

I installed LAV splitter + audio (no LAV video codec)… and… it worked!  No more drift and bitstreaming is working.  Have yet to actually try something with subs, but according to graphstudio, DirectVobSub is loading so it should work.

Had one little problem with an audio decoder (supporting only stereo) from Remote Potato (a recent addition to my HTPC in the last few days) loading instead of the LAV audio decoder.  For now, I unregistered that audio decoder.  Will have to see if that has broken AC3 decoding for Remote Potato and if so figure out the real answer (I would imagine… reducing its merit).

Thanks for all the ideas and hope my trial-and-error helps somebody else in the future.