Problems with Server Power Control plugin installed on VortexBox is 2.1

I've recently installed VortexBox is 2.1 software on an old PC and am struggling to get the Server Power Control plugin to work. It seems to be installed as far as I can tell, but doesn't shut down when the Squeezebox Touch or Boom is switched off.


If I enter the following command sudo -u squeezeboxserver /usr/local/sbin/spc-test.sh

I get....

"Broadcast message from squeezeboxserver@vortexbox.localdomain (Sat Aug 25 22:59:
42 2012):


************************************************** **************************
***************** THIS IS A TEST ******************
************************************************** **************************

This is a SrvrPowerCtrl test of user squeezeboxserver's ability to
execute scripts on vortexbox.

You may now see a message announcing immediate shutdown of this
system. vortexbox WILL NOT really shutdown.

************************************************** **************************
***************** THIS IS ONLY A TEST ******************
************************************************** **************************

Broadcast message from squeezeboxserver@vortexbox.localdomain (Sat Aug 25 22:59:
47 2012):


************************************************** **************************
***************** SUCCESS! SUCCESS! SUCCESS! ******************
************************************************** **************************

Success! User squeezeboxserver has passwordless permission to
shutdown vortexbox.

This test script, in voluntary cooperation with your operating system, has
has been developed to inform you of permissions problems. Had this been
an actual shutdown event, your system would have halted by now and you
wouldn't be reading this.

This concludes this test of squeezeboxserver's ability to run privileged
commands on vortexbox."



Also if I enter the following I get the below

sudo -u squeezeboxserver /sbin/shutdown -h now

[vortexbox.localdomain ~]# sudo -u squeezeboxserver /sbin/shutdown -h now
Must be root.

Any suggestions on how I can get this working?

Many Thanks