I've experienced this issue time and time again with many different macbooks & macbook pros. The part apple chooses to use for the superdrive is not reliable in the long term compared to other drives. I'm not sure if it is a common trait of trayless optical drives, or if it is just this particular part, but in my repairs I notice it has a much higher failure rate than comparable laptops with tray-loading drives.
If Apple will honor the warranty(if it's still under warranty), and you can work within their timeframe, have them do it. Typically this is not the case(or else I'd have to find other work). If you're on your own, here's what I'd do.
If you
search ebay for uj-857-c, which is the part # of a truly compatible part, you will find what you need.
here you can buy it in the U.S. cheaper than from anyplace else, and priority mail gets things to you in 1-3 days, not the 4-7 UPS takes. I would buy it there if you plan to do it yourself. I have bought from them before when I needed something quickly, and their parts were great.
Don't bother with other "compatible" panasonic models, many vendors advertise compatibility with cheaper $23-$30 models for all powerbooks & macbooks that
do not fit physically & do not have the proper connector. There is one other model that is a DVD burner as well that fits but there are many others that do not. Most vendors are absolutely clueless - half do not employ someone who can speak proper english, much less try parts prior to advertizing. I speak from experience, it is worth it to just get the known compatible part.
Installation is not difficult. You remove the top case, remove the hard drive, unplug 3 cables then remove the superdrive. There are 3 screws holding it in. You remove them, and take the bluetooth antenna & its holster off the drive. You remove the 2 or 3 mounting brackets from the old drive and put it on the new one, and install the new one. The mounting bracket that screws to the bottom of the case is a bit hidden by 3 cables, thank Apple's design team for this wonderful experience. You will be reusing the bluetooth antenna holster, mounting hardware, and drive cable, so keep those.
In my experience, it's less than 10% of the case that the drive needs to be cleaned opposed to replaced. With other laptops, I would say go with a cleaning, but this part's failure rate with me makes me say replace it.