Is anything showing in /var/log/lightdm that indicates LightDM is involved?
** Changed in: lightdm Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-screensaver in Ubuntu. https://bugs.launchpad.net/bugs/1543782 Title: Complete system freeze some time after lock screen starts To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1543782/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs