Update 21 Kills Flash in Safari

Hello, I have been a mac and safari user for a long time and I have never really had a large issue with flash before this past week.  I recently updated my Flash Player plugin to the latest version, and since then, I have noticed flash eating up 100% of my CPU sometimes when I open tabs from various places around the web.  It seems to come and go at random depending on what websites I visit, and the websites that trigger the overload seem to change every day.  Below is a list of all of the things that I have tried having spent 2 hours on the phone with Apple Support.  I have also included the details of my system.  Any help for this issue would be appreciated.

Items Tried with Apple Support

• Restart Computer
• Clear Cache
• Clear junk files
• Cleared browser history, data, and cookies
• Force quit and restart Safari
• Uninstall and reinstall flash player

System Details

• 15" Macbook Pro w/ Retina Display (mid-2014)
• OS X 10.11.5
• Safari 9.1.1
• Flash 21.0.0.242