Safari will not play Youtube videos!!!

I had this issue.... Apparently, Youtube put me into an HTML5 Trial.

So after uninstalling reinstalling, emptying caches...it was Youtube.

went to here to get out of it http://www.youtube.com/html5

This solved my problem. Restarted Safari before going back to YouTube and all is well. Thanks for the info!

Alright lee...after days of struggling and trying everything but throw the computer out the window, simply leaving the html5 trial was it!!

Thanks. Getting out of HTML5 trial in YouTube solved it. Still strange why it wasn't a problem before or on my late 2008 MBP, but only on my new iMac i7. Different video hardware causing the problem?

The developer of http://www.verticalforest.com/youtube5-extension/ should be awarded a medal for making my 4 years old MacBook Air play videos perfectly again AND not making it crash after 10 minutes of watching Flash videos on Lion. Not all sites, but I certainly use YT a lot and even 1080p videos stream smoothly.

I agree... the YouTube5 extension is great! In response to others, I was never in the HTML5 trial and was having problems with YouTube, so that wasn't the problem for me (although it sounds like it was a problems for others). Things seem to be working now since the latest flash updates, so I'm guessing that was the problem.

Thanks for the tip. Turns out it was indeed incompatibility between Safari and YouTube html5 trial. Ironic.

We have a winner! A thousand thanks @leejbarker32! A thousand thanks.

It did work for me, thanks!

Fantastic. Worked perfectly. This issue was completely trashing Safari. Why/how on Earth has this situation occured? Surely YouTube/Google/Apple should make people aware of it. Certainly Google/YouTube should advise people that they are part of the HTML5 trial as I certainly don't recall agreeing to participate!

Anyway, thanks very much for completely fixing this crazy issue.

You are 100% on the money! I feel like I am in that commercial for cell phone beta testing. I didn't know I was beta testing!

Thanks a million. While I would prefer to be on HTML5, I'm not interested in a broken player.

Thanks

Beware everyone that Google put me back in the HTML5 after I opted out. I've now opted out a second time so we'll see how long it lasts.

Thank you, Lee (leejbarker32). Leaving YouTube's HTML5 Trial has solved my problem as well. It started a few weeks ago and I couldn't figure out what was wrong.

YouTube videos under 720p were no longer playing in Safari. While they played fine in other browsers. If I changed the video resolution to 720p, they would play in Safari but that is not always an option. I can't believe how much time I wasted in trying to resolve this issue.

I completely forgot I was in YouTube's HTML5 Trial. I would never had thought of that.

Now that I left the trial, YouTube videos are playing instantly again.

Thanks again, Lee. 🙂

Thanks for the link! I was signed up for the HTML5 trial as well - which I didn't know about; so I clicked on the link to leave the trial and as soon as I did, youtube starting working again on Safari!

Thanks! Saved my life as well!!