Similar issue as in #1180386: Use of copy() and simplexml_load_file() rather than drupal_http_request() causes Media:YouTube thumbnails to be empty
See attached patch
It happens too when the video is set on private. Did you try the patch in #1587686: Private Video Thumbnails Empty - Proposing oEmbed over Simple API?
As Simon Georges mentioned, this is a duplicate of #1587686: Private Video Thumbnails Empty - Proposing oEmbed over Simple API.
Comments
Comment #1
ckngSee attached patch
Comment #2
simon georges commentedIt happens too when the video is set on private. Did you try the patch in #1587686: Private Video Thumbnails Empty - Proposing oEmbed over Simple API?
Comment #3
devin carlson commentedAs Simon Georges mentioned, this is a duplicate of #1587686: Private Video Thumbnails Empty - Proposing oEmbed over Simple API.