S/PDIF passthrough issues

Is anyone else having major issues with S/PDIF passthrough for AC-3, DTS, or other digital audio in Windows 8? I can't seem to get any computer working correctly with passthrough. Using passthrough results in extremely choppy playback or artifacts on screen. Tried MPC HC (internal and directshow (ffdshow,ac3filter)) and VLC.

PC should have more than enough power to playback the files and passthrough works correctly in Windows XP, Vista and 7.

 

You need to manually enable S/PDIF passthrough with VLC. Same chip and same drivers as mine. There are no issues if I disable passthrough.

Shouldn't be a codec issue as VLC only uses internal and that/those codec packs use the same filters I've already installed or tried. Audio drivers are latest.

EDIT: To be exact. MPC HC reports a lot of dropped frames. This doesn't seem to happen on all videos, but if it does, it happens only when using S/PDIF output.
EDIT2: Culprit appears to be the text subtitles in MPC-HC (DVB/picture subs are unaffected) and strangely only with S/PDIF passthrough with AC-3 or DTS audio. I have a time and date displayed as subtitles even in my home videos, so that was causing it to appear "everywhere".
EDIT3: It seems that MPC-HC has issues with subtitles with or without S/PDIF enabled and VLC only has issues with S/PDIF enabled.
EDIT4: MPC-HC issue fixed by using external subtitle renderer. hxxp://code.google.com/p/xy-vsfilter/wiki/Downloads?tm=2 Hopefully this will be helpful for someone dealing with this. Can't do anything about VLC though, other than not use S/PDIF. So really the issue here was about subtitles and not S/PDIF output.

 

Okay, too much editing. Time for a new reply.

There (probably) seems to be an issue with some nVidia graphics cards that causes subtitle rendering, or something that's related to rendering text subtitles (srt, txt, ssa, ass) in MPC-HC to act the way I'm describing (dropped frames -> choppy playback/artifacts/etc.). The fix is to disable "allow animations when buffering" from view -> options... -> subtitles. An alternative fix is to enable animations and set buffered subtitles count to 0 (10 by default). Then you can also try deleting D3DCompiler_43.dll and d3dx9_43.dll files from the MPC-HC install directory.

Probably the same thing that's messing with MPC-HC is messing with VLC. What that "something" is, I have no idea.


EDIT: A mod could maybe rename the thread to mpc hc choppy playback or something as this really isn't an issue with s/pdif output.