I don’t have a full grasp of whats happening. I “get” that the first reply is thinking that the source clips frame rate has to be “constant”, otherwise the video will shift/drift w.r.t. the audio.
But that does not explain why, in my case, exporting for YouTube was fine. I’m still trying to figure this out. I posted that FAQ about how to export which says to press RELOAD first. I cant find that button, just RESET. RESET seems to blow away the preset, back to the project defaults. So now I’m confused.
Ah, here is somebody back in 2018 asking about “Reload” as well!
@RickS Your problem is not exactly the same as mine, so you might want to start a new question with it. Otherwise, advice meant for my problem might mess you up.