Looking at your site, you have a CDN extension enabled which is improperly changing our link to the Facebook Javascript library. If you open the HTML source on your page and search for "connect.facebook.net", you'll see:
js.src="http://cdn.<YOUR_SITE>.com/connect.facebook.net/en_GB/all.js"
That line should look like:
js.src="//connect.facebook.net/en_GB/all.js"
You'll need to configure your CDN extension to not include that file or contact the extension developer and let them know that they are improperly converting scheme-less links (ones that start with // and no http or https) to use your CDN. They should not be modifying those links.
Hope that helps, but if you need more info, let us know!
Alex
File does not exist: /var/www/html/connect.facebook.net
