Comment 5 for bug 1611162

UPDATE: I think I discovered the "root problem"! it looks like the "Screen Off after xx minutes" function, combined with the "Require password when waking from suspend" option checked (System Settings, Brightness & Lock) is causing the problem. The attached screen capture shows the relevant settings. DATA: I DISABLED the "Screen off" function ("Never" option) and un-checked the "Require password when waking..." option, then activated the Screen Lock and "let it sit". I was able to exit Screen Lock via my password. I then re-enabled the aforementioned "Brightness & Lock" options (see the attached Screen Capture picture for the settings) and THE PROBLEM CAME BACK! when I enabled Screen Lock, the screen "faded out" then the monitor went into "power save" mode (i.e., "no input signal detected"). I then moved my mouse/"worked" the keyboard, and the display NEVER CAME BACK - I had to reboot (via RESET button) to regain functionality.

For the record, BEFORE the upgrade from 14.04 LTS, the system was set to use the aforementioned "Screen off..." and "Require password when waking..." functions and there were no problems in coming out of Screen Lock by moving the mouse/"working" the keyboard.