None of the solutions on here have worked for me. Recently I've installed Lubuntu. I'm getting used to DE (switched from GNOME), however, I have a problem with the power management (Lubuntu uses xfce4 power manager). The system does not suspend after closing lid of my laptop (fan is still working, music is still playing) although I have an "operation after closing the laptop" option set for "suspend" in xfce4-power-manager.
Any suggestion to get this fixed is highly appreciated.