as I wrote in my initial post, I did make a movie with numbered frames to check for drops and duplicate frames.
As I wrote in my initial reply, don’t do it like that. Generate numbered frames dynamically, not from a movie. You can’t be sure jitter will play every frame of a movie, or render frames only once.
I can’t give you jitter advice I’m afraid, because I can barely use it myself.
If you have real-world usage of Syphon Recorder with jitter that isn’t working as well as you’d like it to, please e-mail us
The simplest possible Max patch which reproduces the problem
A very short recorded movie and an explanation of what’s wrong with it
A screenshot of the Preferences window in Syphon Recorder with the settings you used to record the movie.