flashplayer doesnt load videos proper on latest firefox

With flashplayer installed whenever my mouse  enter the video window on some sites it makes the video look choppy or it produce a strange behavior like the video will get a black screen as long as the cursor is there, as soon as the mouse is out of the video   picture will show up again normal, you cant interact with the video window in any way.

To give an example i visited the adult site nuvid and in there  every video will look choppy, on xhamster the video will reduce  its window size while being unable to use video menu.

I know flashplayer is the cause because i unistalled it and ran Firefox without it and the videos loaded fine. Now i dont know if this is an interaction that goes wrong between  the latest FF update and flash because i recall those videos  used to ran fine until the last FF update.

Also as a side note you cant  use the web installer (1.1 mb) with the latest  Firefox you will get a permanent program stopped running, i had to  download the standalone installer (19mb) to be able to reinstall.

Please dont post to give me generic responses with useless links or suggest me i disable things on my computer when  everything runs fine on my end.

Am using Win7 x64, Firefox x64 52.0.2 and that latest flashplayer.