I have a 2011 iMac and my Superdrive seems to no longer burn discs. I have tried both Verbatim AZO CDRs and Maxell CDRs. Getting write errors with both. The Verbatim's are some of the better blank media you can get so...I'm stumped. Have tried cleaning my superdrive with a can of compressed air to no avail. I purchased AppleCare+ when we purchased the Mac, exactly 3 years ago to the month. I think I'm past the expiration on it though. I'm thinking about just purchasing a stand alone optical drive, any suggestions?