I found a solution, download the YoutubeCenter extension from here.
https://github.com/YePpHa/YouTubeCenter/wiki. It lets you set your default player to flash, as well as a ton of other options, It replaces Youtube's settings, so when you click the setting icon in the top right of a youtube page it brings up the YoutubeCenter preferences.
No more HTML5 player. Nothing against HTML5, but it was giving me all kinds of problems.
Progress bars wouldn't go away.
The end screen for videos didn't work (sometimes I actually watch the suggested videos.)
Clicking back on the browser after the video was done just played the video again instead of going to the previous page.
Im sure there are more issues, it's worth a bit more CPU usage to use the flash player. Never thought I'd say that lol.