I bought a refurb 24 inches iMac this week from the Apple store and everything seems to be working fine except it keeps ejecting installation CDs! It did that for the installation CD of my HP printer and it's now doing the same thing for the installations CDs for the wireless mouse/keyboard. I tried putting a movie in it and it worked but for some reason, I can't get it to read any install cds... Is there trouble in paradise?