VIDEO'S from YOU TUBE showing fine and playing on my end on my computer
Currently running Windows 7 home / with high speed cable Road Runner internet
check your security settings maybe

?
check the internet settings , any check marks in boxes that don't let videos play on web pages

?
did you do any recent Windows updates that changed settings without your knowledge,,,,
I have 1 local news site that I can't get their videos to play, , the screen just goes black, tho I get the sound, but no video.
I know theres been some changes with Video players in the last few months,,,,
Also I'm NOT using Google Chrome for an internet browser
I'm using internet explorer 11,,,,, which seems to be working just fine with everything else at the moment,,,,
As well, videos on Just Flight Forms play well on my end too
as well as Air Daily X web site that have YOU TUBE Videos embedded into the web site from YOU TUBE,,, no problem on my end..
other YOU TUBE Videos in this forum board play OK on my End as well,,, no problems, even tho there NOT my Videos , but other flight simmers.
dunno' guys,,,, I'd start with checking some of your internet settings and security settings,,,, go from there,,,,