is that it's Adobe Flash related. That doesn't mean it's a sure thing but when you consider that Apple and Adobe do NOT play well together... and Apple has done everything in it's power to eliminate Flash from their devices/os's... it's likely.

Try this, if you haven't.... click SAFARI then PREFERENCES. The click the SECURITY tab when the new window opens.

you'll see a PLUG-IN SETTINGS.. click that and then ON THE LEFT make sure Adobe Flash is turned on. I'm not sure about the setting on the right where you set it to on or off.. mine is OFF but I still see the videos. My setting on the left for Adobe Flash is clicked ON. - JamesJM