Course freezes online before video

Hi, one of my courses includes a youtube video and has worked fine upon previewing, publishing and uploading online as a scorm file.

However, I wanted to change the youtube clip to a newer version, so made the edits, previewed the whole module - works fine, then published it and previewed the html file and there's an issue. The course freezes on the slide just before the video after the user clicks the next button. I check the old version of the course (still live thankfully) and it stalls for a few seconds before changing to the slide with the video on it, but it doesn't freeze.

I also tried removing the video completely, publishing and previewing the file, and the whole course works fine with no freezing.

Has this issue occurred for anyone else previously? And is there a way I can fix it?

Thanks!