Since upgrading to starch, when I click the button in Gnome to shutdown the computer, the screen turns off and the computer stays running (i.e. I can hear it). It used to be that the normal behaviour was a bunch of messages on the display, and then the computer shuts down about 20 seconds later. But now the screen stays black, and the noise of the computer keeps going. I have to hold down the power button on the PC to force it to turn off now. I don't even have a clue where to start with troubleshooting this. Can someone help please?