Videos auto playing in FF, despite being set not to

[jnelsoninjax]

I am noticing that some sites that I visit have embedded videos that start automatically despite the fact that I have set the option in about:config to not auto play videos. Now other sites, such as Youtube, the videos appear to start automatically, but they are not playing unless I pause and then UN-pause the video. Can anyone give some ideas as to why this is happening?

[max22]

No idea but I use Flash Control addon to stop autoplay of html5 videos.

[Pork Chopper]

Try FlashStopper.