Youtube: "ERROR: unable to download video"
I'm getting "ERROR: unable to download video" for youtube downloads.
The issue is fixed upstream in https:/
The diagnosis there is that 'this is a strange case where the "best" codec only has "mobile" quality'.
This is related to some sort of change in youtube which has resulted in the same kind of problem that was resolved for bug 915029.
See also: youtube-dl is not working - Ask Ubuntu
I ran into this on precise, but the same bug will exist for all Ubuntu releases.