YouTube iFrame Players created using the iFrame API are now broken in IE 8, 9, 10 - though none of the code has changed on my side. It also seems that the issue exists with other embeds.
This YouTube demo, for example, doesn't work in IE: https://developers.google.com/youtube/youtube_player_demo
The video plays for a few seconds and then switches to HD and then errors out.
Any solutions would be appreciated.
I had the same problem today. When you listen for the onStateChange event, the event.target YouTube player dispatched to this event used to have an numeric .id for each embed on the page, and that ID seems to have disappeared.