output subtitles still out of sync

Upload a tarball with debugging information

1. Run the command that produces the out-of-sync subtitle output, but with the additional --make-test-case flag, i.e.: subsync ref.mkv -i in.srt -o failed.srt --make-test-case
2. This results in a file of the form ref.mkv.$timestamp.tar.gz or similar.
3. Please upload this file using the "attach files" button at the bottom of the text prompt.

That's all! Thank you for contributing a test case; this helps me to continue improving the sync and to add additional integration tests once improvements have been made.

Additional context
Add any other context about the problem here that might be helpful.

Bob's Burgers - S12E02 - Crystal Mess WEBDL-1080p.mkv.2021-12-29-21-24-15.tar.gz

This file was generated via Bazarr. Bazarr reported that there was an 'offset of 0 seconds and framerate scale of 1.0' when they're about a second out of time.

Start with the attached debugging tarball and reproduce the report using the subsync ref.mkv -i in.srt -o failed.srt --make-test-case command described in the issue. Compare the generated subtitles with the reference video and determine how the reported one-second mismatch can be covered by an integration test.