Ipod not being recognised, but with a twist

Hi,

My ipod nano 5th Gen is not being recognised on my computer. It is now being recognised by the computer itself sometimes, but not itunes. However, when I plug my ipod into my partners laptop, its fine. More to the point, when they plug their's into my laptop, it recognises them. To me, this suggests that both my laptop and my ipod, individually at least, are working.

I have been through the ipod support page, and gone through all the steps, and to no avail.

Final details. I'm Windows 8, and my itunes is totally up to date. I have re-installed iTunes, and have reset my ipod to factory settings on another computer. It still doesn't work, please help if you know anything about this!!

Cheers,

Ralf