I recently formatted my sisters computer so I could use it, and for some reason my CD/DVD burner wont read DVDs. I have burned CDs okay with it, but it doesn't read when I put a blank DVD in. I've tried multiple blank DVDs and multiple brands, it wont read anything. The drive is NEC DVD+RW ND-1100A 10GE.. I just upgraded the firmware thinking that might be the issue but the problem still persists, any advice?