Latest Firefox causing AV receiver/projector to freak out.

[MowgliCSM]

I have narrowed this issue down to HTML5 video. This will happen with Youtube, Twitch or even GIFs. Whenever I access these, it will cause an interruption to my A/V receiver/projector on my home theater PC, causing my projector to search for a source and the screen to go black. If I pause the video and open a new tab, after a while, the screen will flash, go black, then come back. If I go back to the tab with the HTML5 video it will cause it to do it again. This all began after FIrefox updated to 51.0 build 20170118123726. If I turn off hardware acceleration in the advanced options it will no longer happen but then I get terrible screen tearing when scrolling on pages. I have installed a toggle HTML5 video extension and is works fine with it disabled but then I have to play everything in Flash and it causes some GIFs to not even show up.

Let me know if you need any more info and thank you for any help.

[therube]

(Those "GIFs" are probably not .gif, but actually HTML5 "movies", & that's the reason they no longer work when you disable HTML5.)