There is a bug upstream about that: http://bugzilla.gnome.org/show_bug.cgi?id=332974. It's closed and states it's not a totem issue. Could you try to use "dbus-monitor --session" as suggested upstream and note what is happening?
** Changed in: totem (Ubuntu) Importance: Undecided => Low Status: Confirmed => Needs Info -- [edgy] Screen blanks when watching movies https://launchpad.net/bugs/66257 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs