Desktop blinks under non admin user account

Hello all,

I've got this strange problem with an XP machine I have on my domain.
On this machine, the desktop seems to randomly refresh when a non
administrative domain user logs on. I've tweaked some things in group
policies, and the local machine to get it to start without themes and
in classic mode. I just can't seem to get it to stop blinking at random
though. If anyone has any help for me, or could recommend a better
group for this kind of question, I'd love to hear from them.

Thanks,

Evan