One Minute of Audio, Three Runs: 13 Segments, Then 9, One of Them 21.94 Seconds Long

Same file, same build, same input, three runs. The words moved by one comma and one space in 215. The segment count dropped 44% and the longest segment went from 5.32 to 21.94 seconds — which breaks everything downstream that keys on segments, starting with subtitles.