Disable Beep/Bell Sound on FreeBSD
This command would disable the hardware beep/bell sound for the current session.
sysctl hw.syscons.bell=0
If you want to disable the beep/bell sound persistently you should add the “hw.syscons.bell=0″ entry to /etc/sysctl.conf file by giving the following command;
echo “hw.syscons.bell=0″ >> /etc/sysctl.conf