Youtube HTML5 player video turns blank

Recently youtube changed from flash video player to html5 player and it's causing all kinds of problems. Most importantly that when playing videos after a few minutes the video simply turns blank, the sound is playing but there is no picture. Not even if I try to seek in the video or restart the playback. The only way to get the picture back is by re-loading the page entirely.

But the ideal solution would be to get rid of html5 player entirely as the picture quality is noticeably worse than with the flash player. I clearly see a huge difference when I switch from html5 to flash by using an extension. Which is a shame because the html5 player seems more stable and more responsive compared to the flash player, but I won't compromise on PQ.