It is a Bug Status: Assigned please check : https://developers.facebook.com/bugs/1503212169899736/
You can work around this by hosting your swf player on Amazon S3 servers . it works for me .
I have the same problem since 21 APR , i tried everything
Try the Debug tool : https://developers.facebook.com/tools/debug/og/object?q= and check if your site enabled -- Video embedding on Facebook enabled --