Hi! I recently purchased a refurbished 24 inch imac from the apple.com store. I've noticed when the computer is idle (black screen), my wired mouse does not work. When I pull the cable out of the usb port on the imac, the computer screen comes on and then I reinsert the cable back into the usb port in the computer to use the wired mouse (wired mouse works fine after I reinsert the cable back into the usb port). Could this problem be associated with the wired mouse or with the usb ports on the imac? Thanks in advance for any any info/suggestions regarding this issue.