Choppy when 200% zoom
 

Whenever I play files at normal size, or full screen, they run perfectly fine, smoothly and wonderful. If I try to make it double size, 200% zoom, it gets all choppy... I don't think i've changed anything, but it didn't use to do this, not to the degree it's happening now, anyway. My CPU utilization remains below 80%, so I have no idea what it could be... This normally only happens on divx files and such, not mpg or asf or non-.avi files. Anyway, is there some setting somewhere or something i could change to fix this? Thanks.