I had the problem some days ago. Then the videos started working again but now the problem is back. Thanks for the tip on changing DNS, videos seem to work fine now that I changed to OpenDNS.
im not in europe, im in the US, but i am having some extreme lag (a lot more then usual)
by lag i mean about every 2 out of 3 videos need to rebuffer
one video i had to rebuffer like 5 times
heres my speedtest.net result
it is typical for me
and a pingtest .net result