Audio track stopping short after Share in QuickTime MOV and MP4

I am brand new to this software and on my first attempt, I am experiencing the audio track stopping before the end of sequence when playing back the MOV export via QuickTime. The audio is fine when I playback in FM. I’ve also cut an MP4 file and the audio stops short on that as well.
Any ideas as to what I’m not doing correctly?

Is it possible for you to share the slideshow somehow so we could check? You can also upload it to e.g. wetransfer.com and send the link over email to support@boinx.com, mentioning this forum thread.