i'm having an issue that manifests itself with a grey screens for a few frames when encoded with av1an (available on github) piping video thru VapourSynth to aomenc ONLY when ripping thru (current) MakeMKV but not with my old AnyDVD HD feeding mkvtoolnix the m2ts.
annoyingly, it doesn't show up when you do a straight encode of the problem rip with ffmpeg ...but it DOES show up when stepping backwards thru the MakeMKV-ripped movie with say mpv (and of course in the encode done with Av1an, which chunks up videos to encode in parallel with codecs that are poorly multithreaded like most AV1 encoders currently are)
this hasn't happened with the other couple discs i've ripped with this version of MakeMKV. oh, and i make sure AnyDVD HD is disabled when ripping with MakeMKV
chunk of the MakeMKV rip: https://mega.nz/file/OQpSVQ6R#7vG31WlnY ... cOWqsOQJBA
chunk of the m2ts ran thru AnyDVD HD chunked by mkvtoolnix: https://mega.nz/file/OI5yBCaC#bHOYdrhwb ... lwtQE3SHiM
approx timestamps of problem frames (at least in encodes): 0:23, 0:42, 2:49
example of transcode showing issue (mpv/mpc-be/vlc needed): https://mega.nz/file/XNwWyRDY#guFQ-eOo5 ... bdzKKPP5qI