Editing the caption only updates the on-screen text — it doesn’t modify the actual voiceover.It’s useful for correcting any words the AI may have misheard or misspelled in the subtitles.
See: Magic Captions
It's not possible to edit a voiceover once the AI video has been generated.However, you can generate a new voice clip and replace the incorrect voiceover by going to the text-to-speech section.
See: Text-to-speech