Hi @Jeroen.
I made a test with your video source… it was not necessary since it is a simple YouTube video but, as you can see in the link below, it is working as expected in my test page.
That means that it has nothing to do with the plugin, you have to find the problem somewhere else.
I can see that other videos works fine in your site; is there any specific code in that page? Is it using the same header?
