I have the same issue which I mostly notice with MSN. Tried with and without flash player enabled and with the ad blocker enabled and disabled. Seems to work a little better with flash disabled but not always and if if does work it is after a long delay before starting.
Latest posts made by aaronaard
RE: WHY WON'T VIDEOS STREAM?Opera for Windows
MSN Videos Not PlayingOpera for Windows
For the last several days, I have not been able to play most videos from msn.com The video will play a couple of seconds, dissapear and then display this "We're sorry, an error has occurred when playing video (video is not supported).
This happens with Beta version 40.0.2308.15 and the latest stable 39.0.2256.48. I have the latest flash player installed and enabled 22.214.171.124. MS Edge and firefox work. Chrome does not play but there is no error.
I am not sure but it is possible there was a flash player plugin about the time this first started.