MPC-HC & MPC-BE Users:
Failure to do so with
xy-VSFilter (VSFilter.dll) will result in it being
blocked and not used.
Failure to do so with
XySubFilter will in result in
horrible performance since the ISR will be rendering subtitles with madVR at the same time as XySubFilter.
If you are not achieving near-identical performance with XySubFilter+madVR compared to xy-VSFilter+madVR, this is the most likely reason why.