Thanks for your help, I applied: Option "AccelMethod" "glamor" Option "DRI" "3"
in /etc/X11/xorg.conf and rebooted (noting that lxdm didn't shut down properly), which seems to have stopped the need to switch to vt1 and back to vt7 because of stuck windows. However, having done that even without logging in to a graphical session (ie, just normal boot-up), I can't successfully run: service lxdm restart and have to kill -9 the Xorg/lxdm processes before running: service lxdm start to successfully restart Xorg/lxdm I haven't triggered video playback problems since the changes to xorg.conf so far. Arthur
