This seems to be a common problem (Optical drive not reading DVDs)

So my MBP stopped reading DVDs the other day but still read CDs. After many google searches this seemed to be a common problem. From what I've read the solution was to either clean the drive or to get it replaced. After cleaning it, it still failed to read DVDs so I got the drive replaced. Now with a brand new drive it still doesn't read DVDs. I take it there is some sort of software problem, I am not very tech savvy and I couldn't find anything on the internet about this so I was wondering if anyone has any advice?