Youtube embed not working in firefox

Question

I have Embedded three Youtube videos, they work perfectly in ALL BROWSERS except Firefox.

Tried clearing cache on server side, cleared cookies & cache locally, t

Answer 1

Found this on a website hope it helps:

Seems that the problem occurs only when youtube shows the flash version of video, while with html5 it works. You can force YT to serve the html5 version of the video adding this to the iframe embed code: html5=1

Consider also that if the html5 version of the video for Firefox is not present, YT serves however the flash video as fallback. So the issue is surely related with flash.

//edit changed &html5=1 to ?html5=1