Using a Philips screwdriver, remove the two screws on the top of the device, towards the back.
Remove the plastic cover by pulling up on the back and away from the faceplate.
Remove the faceplate by unclipping the latches on the bottom of the device.
Once it's unlatched, pull the faceplate off.
Locate the optic lens in the middle of the disc drive. Dip a cotton swab in rubbing alcohol and use it to lightly wipe the lens. After the lens is clear of dust and debris, wait a few minutes to let it air dry.