[HELP] the speed changes

[david]

Without a debug output, like mentioned in the sticky.
My guess is that your source is vfr, but mediainfo doesn't detect it as such. Enable the timecode extraction for all files under Config->Misc->Automation sonewhere and try whether that helps.

cu Selur

Dear selur 
Thanks for reply,
I enabled the the timecode extraction, but still have the same problem.