So I got my mom an emac from work a while ago for cheap. I upgraded the stock CD reader to a Samsung SM-308 CD-R/W DVD combo drive. It worked great for about 2 months, then all of the sudden it stopped reading CD's. DVD's worked fine, but CD's would not mount. I tried to run a laser cleaning disc, but since it was a CD it also wouldn't mount. Naturally I replaced the drive. I got another drive exactly like it for free from work, and put it in today. Still has the same issue. I also tried wiping the HD and reinstalling the OS and it still won't read a CD. So what should I do next? Thanks!