going to give the usual "sorry if this is somewhere else" because I feel I can't be the only one with this problem, but I honestly can't find it anywhere.
When applying effects (specifically noticed with Levels), sometimes - not always - as soon as the effect is applied, even before changing settings, it causes the video to slip a frame.
See this link for an example that I was working on today https://vimeo.com/178948037/06cc5b4024
Many times it doesn't matter at all, but other times it can really mess things up, and rather than a work-around (which is a simple slip edit) I'm more wondering why this happens. It's been happening off and on for at least a year for me, I'm just finally getting to actually posting about it.
For settings, etc:
Sequence is DSLR editing mode, 1920 x 1080 progressive, 23.976fps, 48kHz audio, composite in linear color is checked
Footage currently being used is from a Sony a7s, shot 60fps but conformed in PPro to 23.976
You can also see that the clip being used does have a speed adjustment on it as well. I did try nesting it, but strangely, that also caused a frame shift.
Can't recall offhand where the footage came from in previous projects that this has happened with.
After typing this out, it seems like it has to be something with the different frame rates and speed adjustments, but I'd definitely welcome any thoughts.