Superdrive is not connecting through USB
My superdrive is not showing at all in Finder. I know there is a disk inside the superdrive because I hear it when first connected to the USB, but then nothing. I have already gone into the Finder Preferences and checked the CDs, DVDs and iPods line under Devices. There are two USB ports and it does not work in either one. This has happened before. Also, I have experience a couple of times when the USB ports would not read a flash drive. This is all sporadic.
I am on a MacBook Pro 13" Retina, 2.9 GHz, 8GB of memory, that is less than 6 month old. My software is updated 10.11.13. Please help.