PowerDVD and Limited User Account

I have two user accounts on my machine - an Administrator account and a Limited User account. I mainly use the Limited account unless I'm installing software.

When I use PowerDVD 6 Deluxe to view a DVD on the Limited account, my system becomes sluggish after a while. For example, maximizing and minimizing the PowerDVD window takes ages with a lot of disk access while the Desktop is being redrawn. When I view a DVD under the Administrator account I don't experience this slow down.

I'm guessing that PowerDVD doesn't have privileges to access a certain resource causing the slowdown and disk access.

Anyone know what's going on and how I can improve performance under Limited account ?