Hello Pool... Try Clearing data on Youtube app, here is how to:
From Home Screen>Settings(two cogs)> Other>More Settings> Apps
Or From Home Screen>Settings (Two Cogs)>Apps>
After reaching apps find youtube click Force Stop then click on Clear Data.
Now go back to Home Screen by clicking on the Home Button on remote then Go onto Playstore (shopping bag like icon) then search for youtube and click on it and then if it shows Update click on Update... After update is Complete it will show Open... Now click on Open and see how that works for you.
Also if you are a T8 or T8-S user please update firmware on your box and see if that resolves the issue, here is how to:
https://droidbox.co.uk/blog/t8t8-s-ota-update-12-11-2015/
Hope that helps