The solution to this problem was just a work around. The reason being the that blob servers aren’t streaming servers. iOS devices expect the videos to arrive in small chunks. So for instance a streaming server is able to do this. However, a blob server just hands the video as a blob which is not what the iOS device expects. Some browsers are smart enough to handle this but others not.
The way I solved this was to add the video files outside of the blob server in a folder within the project and then render this through the Apache server instead of serving it via the actual blob server we were using. I hope this helps.