Jordy - you may have said but what are YOU doing when you find the correct You-tube video?
You have to copy the address in the address box at the top of the page, let the video start as that sometimes makes a difference.
The page that I am on just now is
http://www.theanswerbank.co.uk/Music/Question1419523-4.html so you are looking for the same box on the you-tube site.
With my tablet I press my finger on the screen at that point and am given the option to copy the information.
Then I come back to AB and paste that exact address in the post.