Move YouTube content requires the Flash plugin.
Uninstall your current copy of the plugin then reinstall new > Troubleshoot Flash Player | Mac OS
Restart your Mac after you reinstall the plugin, launch Safari.
From the Safari menu bar click Safari > Empty Cache.
Now try a video on YouTube.
10.7.3 and 5.1.3 which I understand are the latest versions. I have tried the uninstall/re-install routine several times and i have also tried repair permissions under Disk Utility to see if that had any adverse effect. Alas, nothing.
The only Plugin I was thinking that might be causing an issue is Flip4Mac. But as that only handles WMV files etc, I cant really see how it would.
What about Silverlight ? Could that be interfering with Flash ?
I have Flip4Mac installed also without any issues with Flash running Safari 5.1.3 on Lion 10.7.3 so I doubt that's a factor.
Check Safari > Preferences > Extensions. If you have any installed, turn that OFF, quit then relaunch Safari to test.
Do you have ClickToFlash installed?
It can be installed as an extenion or found in ~/Library/Internet Plug-Ins ...
Well it seems to be working now. I actually upgraded Flip4Mac and Silverlight to the latest versions, and YouTube is now working.
Not sure if they have a direct effect on the functionality of YouTube on Safari, but it seems to be stable now.
Thanks for your help, I will revert back if it stops working again.
That certainly helped...I think.
Now I have a situation that some videos play, and some dont.
This one doesnt:
This one does:
How strange is that ?
Some's better than none
Try deleting the cache.db...
Go to ~ / Library / Caches / com.apple.Safari
Move the Cache.db file from the com.apple.Safari folder to the Trash and restart your Mac.
~ (Tilde) character represents the Home folder.
For Lion: To find the Home folder in OS X Lion, open the Finder, hold the Option key, and choose Go > Library
I'm running into I think a similar problem. YouTube audio plays, but the video is a black screen. I've tried updating Flip4Mac, deleting my cache.db file, have Click2Flash installed and it usually works.
Any other suggestions? I've seen this issue in the forums as being a 32-bit versus 64-bit issue back in October/November 2011, and again earlier in February. I've tried setting Safari to open in 32-bit mode and that did not fix the problem either.
I'm using Safari 5.1.2 on a 13" MacBook Pro i5 with OS X v. 10.6.8.
I have the same issues with the same YouTube links. I've unistalled and installed and rebuilt permissions all day yesterday and I still get the same results as you. There really does seem to be some kind of conflict with Safari 5.1.3 right now... but with what, I couldn't tell you. Currently I have Safari stripped of all extensions and plugins and it's still buggy as all get out. Sooooo frustrating.
BTW those links work perfectly in Chromium.