hi there, not sure what site the video's are coming from.
i installed "bad piggies 2 HD" on my mobile - initially got ad's so i put on adblock plus (which stopped the page ads) and then the app promptly started doing video ad's..
the only way to stop them at the moment is to stop any internet access.
adblock plus is fantastic - 5 stars for this (i use it on every device) wonder how bad piggies got around you
still, i am sure you will come up with an answer