Quote:
Originally Posted by
tiggertai 
I only have a DVD cleaning disc, which it won't load... just get the Invalid Disc message. It makes a lot of clunking and whirring trying to load DVDs, and yet it plays Blu Rays just fine.
Keep in mind that there are two lasers... one for DVD/CD and another for Blu Ray. I had the same problem on an older Sony BR player, but it happened only for Blu Ray discs, not DVDs. Eventually I replaced it, but a few months ago when I was about to throw it out, I decided to open the thing up and clean the lasers, for real. Put it all back together, and sure enough, it plays Blu Ray discs again. So now I have a backup if/when my 470 starts acting up.

You may not be confident in your ability to open something like this up and clean it, but if it plays one type of disc, the drive mechanism is fine, the laser is just dirty enough to cause a problem with reading the disc. The disc cleaners are rather worthless, by the way. You could try blasting some compressed air in there, in case it's just a piece of dust, but that could also spread around dust so it's a crap shoot. To really clean it well, it takes rubbing alcohol and a cotton swab. But that means being actually able to see where the laser is...