A sequence I cut to a music bed was three frames out at the first transition, nine at the second, and by the sixth segment nothing lined up with anything. I had asked every generation for ten seconds. Every generation had returned a file that was not ten seconds. Nothing in the API said so. The request took duration: 10 , returned 200 , and produced an MP4 whose container duration was 8.708 . No warning field, no note in the response body, and — the part that actually cost me the afte...