IE 11 Displays "!" During Video Play

[poolmon]

While playing a video in IE11 the video will suddenly be replaced by a static "!" symbol and all the other video links on the web page disappear and also display that same symbol. This happens on only IE11 and on multiple computers. Firefox & Chrome work OK. Flash player is up to date. What's going on with IE11?

 

[UsernameIssues]

What is one website where this is happening for you?

What antivirus app are you using on these computers?