After installing Ubuntu 13.04 (not upgrading to it, I did a "clean install" removing the older one), I'm not been able to shutdown the system.
After clicking the Shut Down button the desktop environment is terminated and the Ubuntu splash screen blink on the screen and a error in a black sceen (without the DE) just says the following:
acpid: exiting speech-dispatcher disabled; edit /etc/default/speech-dispatcher
sudo shutdown -h -q now. Does your system shutdown?