System Reboots after Shutdown

[Motozenmaster]

Running Ubuntu 11.10 on a Shuttle SH67H3 with a Intel H67 chipset and an I5 processor. When I shut down using the shutdown menu option the system shuts down and immediately reboots. I have to hold down the power button to get it to shut down permanently. However, when I issue the following command:

sudo shutdown -h now

The system shuts down normally without rebooting. Any ideas?

[ConfusedButEnthused]

:popcorn: Thank you. I will try that command you mentioned. I have same problem on an eMachine T3882, Intel Celeron D, upgraded 2GB RAM, upgraded 512MB Nvidia video card (required to get Unity to work). I also have Restart hanging without actually restarting, causing me to use button to force shutdown.