FreeBSD Jail Allow Sound And Flash Access

I am running KDE desktop within FreeBSD jail. How do I get audio working from inside the FreeBSD jail so that flash will also work?

The devfs provides an interface to manipulate properties of devfs for jail. It can be controlled using /etc/rc.conf file only. First shutdown your desktop running inside the jail. You also need to stop jail service
# /etc/rc.d/jail stop
Edit /etc/rc.conf as follows:
# vi /etc/rc.conf
Append the following config directives:
jail_xfcedesktop_devfs_ruleset="devfsrules_desktop_jail"
Note: replace xfcedesktop with your actual jail name. Save and close the file. Start the jail, enter:
# /etc/rc.d/jail stop