Pausing in iMovie

I am trying to trim a video, easy thing to do right? Wrong!

While the trim is fine I’ve found that for some reason the movie is automatically pausing at one point, this is preventing me from exporting or saving the video.
I have tried two different iPads, and have downloaded fresh copies of the video. It plays through fine outside of iMovie.

Any idea what may be happening? The pause occurs even with no edits being made. Same exact spot every time.