Assuming your PC has a warranty, you should be able to get a replacement (possibly a slightly better one, if you're lucky) for free by calling the company you purchased it from. Most PCs have a three year warranty, if not a one year at the least. Seven months should fit in that easily.
If this is a customised PC, then your drive should still have it's own one year warranty at minimum.
One other idea would be to try reinstalling the drivers, although I suspect it's the hardware personally.
EDIT: Cleaning the lens may help, but really, if it's seven months old and already having problems, cleaning the lens won't make it last longer than it should. You'd be better off with a replacement drive. If your lens is cleaned, and screws up again five months later, the drive could be out of warranty and then you'll have to shell out. Always - always - better off getting replacement parts during the times you're still able to. I replaced as many parts as I could after three and a half years had passed in my four year warranty. Any slight difficulty was a good enough reason to get them to change it - and they don't generally ask questions (especially if you say that the fault is intermittent - this means that even if they don't see the fault when they arrive at your door, they SHOULD replace the parts anyway... I know this because I manage these kinds of calls).
