LiveUSB Hangs on Shutdown

I have a live USB with Ubuntu 10.04 (created with unetbootin) and uses it on my laptop and desktop. In a very weird case, every time i shutdown/restart/log out live USB when using the desktop, computer hangs. But it doesn't happen when I use my laptop. I'm having normal boot, session and no issues with shutdown. Both computers are less than a year old (desktop is a few months older than the laptop). I tried to switch to different USB ports on my desktop but same problem. Any suggestions?

P.S.
Even Puppy linux live usb doesn't boot with my desktop. But liveCDs work..

anyone?

how can I close this thread?
reason:
no other reply except from me.
solution:
installed 12.04 instead