Odd issue embedding Youtube Videos

This is my third attempt at using EB 5, 3.9 was a lot friednly to use, i understand 5. has more features but the learning curve is steep.

What does not help is the way EB 5 works differently it appears on each setup.

Having updated my dev version of the site to V5, i was able to use the inbuilt editor to embed a video from youtube. This worked fine with no issues. Now understand the dev version of my site was imaged from the live version 2 days ago, nothing else has been changed since then.

After sussing out all the quirks i backed up the settings from the dev site, and upgraded the live site. I imported the settings and ammended some old posts.

However one post i needed to re-write due to the issue with embedding videos, so i opened up the post creator and selected embed youtube block.

I clicked the position i wanted and pasted the youtube video link which is in the format requested.
The box goes white and states loading embedded player.

Then nothing. if i click on the box again i will either get the green outer border or i will be asked for the link again. If i save and retry the same thing it just does not pull in the video at all.

If i do this on the dev site it pulls it in without an issue.

Both servers are running same os php etc etc its a true replica of the live site.

The dev site i updated by uploading the component, the live site via the api key and web install that was the only change.

Im creating this is superuser so no iframe issues etc