Keynote 13.2 (7038.0.87) stops playing audio across slides before audio is complete then restarts audio file

I've created over 50 song lyrics videos from Keynote presentations, and the workflow has worked perfectly until now: paste an M4A or MP3 file on the first slide with "play audio across slides checked," copy and paste the audio object to all the slides in the presentation, record the presentation, export as a video.

The latest attempt quits playing the audio at slide 44 and restarts the audio file after a few seconds of silence.

I'm switching to Adobe Premiere Pro to finish projects from now on. So much time wasted on this current project.