Thanks for the answer, but my iPad can play the same video on the same internet connection quite well. I guess I will reload my system by way of Time Machine to a date prior to the beta and see what happens. My original reply was hoping that someone who had a similar problem had a simple fix.
thanks!
I don't think that playing it on your iPad can isolate the issue as being related to the beta build 10.10.2, unless you found a way to install Yosemite on your iPad. (if you did, I am sure that many people on this forum would like to try it.)
Have you checked to make sure that everything else is up to date? (i.e.: your flash player and other stuff that is installed?)
Have you tried a different browser? Are you using Safari? Try other browsers, like Chrome, Firefox, Opera, etc... to see if it is isolated to Safari.
Do you have any adblockers installed. It's possible that you might have some software that is blocking the videos. Disable any adblocking extensions. If you have a "modified hosts" file, try replacing it with the original, and see if your issue clears up.
You might want to install MacUpdate Desktop, run it and see if any of your software is out of date. (please no jabs about installing useless software)
You can also install EtreCheck, it might give you a clue about something that may not be compatible.