The CPU beep is a really irritating thing in Linux distros and sometimes the graphical sound manager does not work when shutting it up.
Fortunately there is a simple way to do it in terminal. In Ubuntu (and distros based upon it) type:
gksudo gedit /etc/modprobe.d/blacklist
In Debian type:
If you are new to Ubuntu, it would be good if you read this Ubuntu, Debian Linux introduction. Its a descriptive explanation regarding Ubuntu, Debian and Linux general. Ubuntu is a Debian based Operating System that is currently become the most popular Linux distribution.
Ubuntu is an operating system based on Debian GNU/Linux (www.debian.org/).
The Debian release team are sounding the alarm: With only one month left before the planned release freeze, the number of critical bugs in Debian 6.0 Squeeze is still far too high to freeze development and create the next stable version of Debian.