I think I have discovered a bug in the theme.
I am using the web inspector to inspect a real device (my iphone) using the developer tools on desktop.
I am getting an error:
Failed to load resource: the server responded with a status of 503 (HTTP/2.0 503)
wp-content/themes/x/framework/fonts/font_awesome/fontawesome-webfont.woff?v=4.5.0
Strangely enough .woff2 works fine and you can’t actually see a problem on the site. I think the theme is adding the wrong version on the .woff format.
If I change the version to v=4.6.0 manually, then the .woff font downloads fine.
Can you confirm you have the same behaviour ?
Andy