Has it to do with the different URL structure? i.e.
www.youtube.com/watch?v=[video id here]
vs.
www.youtube.com/watch?v=[video id here]&list=[list id here]
Is it that the &list= is getting sanitized out?
Yes, IIRC this has been fixed, but I forgwt where I saw the discussion.
Maybe a version update is in order?