On my pc, my iTunes is about 820GB. On my mac (with iTunes on an external 1tb hd), the drive shows that 960GB is used, but the media itself is still only 820GB. Where is this extra 140GB being used? I will soon run out of space and need to get this figured out. Also, how would I go about moving iTunes back onto the OS hard drive, while leaving tv shows on the external? Is this possible? I cannot move the entire library onto the OS drive as the size is only 500GB.