Hi
I looked in Resolve. Very strangely, some clips are beginning with a TC at 0 (because of the option you told me to put in) but some are not! They begin with the original TC, as if the option was “embedded in the source clip”.
Maybe a bug in Resolve…
But the idea was the good one, thank you very much!
(Well, I have to put each clip to 0, or to try another soft…)