Completely ignore
Mister Hatt. Firstly, this is not the 1990's!
Variable Encodes are quite common and they will through your picture-sequence timing-off!!!!
. would it not be easier to just load it into
AviDemux and Get To Work On It -- the right way?
AviDemux was designed to work in the Y2K ERA, use it!
. it understands AVS, MKv, MP4, Xvid and Divx + variable timings and X264 and Ignores "Alpha 3.11" .. .
. it can work with FLAC, Mpa, MP3, MP2, ACC .. variable timings and AC_5+
. it knows the difference between Constant and Variable encodes and detects "that" while its loading the file.
Virtual Dub, Virtual Dub NAB & MOD never had those as options from the start and, like Mr. Hatt, Never Will!
Your fighting a loosing battle using out-of-date-software to fix that issue
and a lot of good it is using AviSynth as an editors helper ..
.. what screen do you see with AviSynth to let you see how well things are going?
don't make the same mistake twice
Dump
Virtual Dub and
the GHOST; use a real editor/converter -- the people from SONY will thank you.