Course with multiple embedded videos crashing for some users

Hi, I'm keen to know if anyone else has had a similar issue.

I've created a new course in Storyline 2 that's mostly made up of short videos created in Adobe After Effects. Some of the slides have interactive elements laid over the top.

Testing works fine via storyline, and the course works fine for most testers via the LMS, but for some testers, the course crashes. Specifically near the end, and specifically on slides that have both video and interactive elements.

I've raised the issue with Articulate and my LMS provider, but I'm curious to know if the issues simply being caused because I've pushed Storyline too far and uploaded a course that's too big (26mb).

Thoughts?