I've done several searches here and elsewhere, but haven't found anything with general advice. I have hundreds of DVDs and care for them obsessively -- not one shows a scratch or fingerprint (some I've had for years). But I've started to discover that a few DVDs which played fine when I first bought them now won't play, or break up at some spot and ultimately freeze. I don't know whether it's the dreaded "DVD rot" or something else (my player's a 1999 vintage Sony DVP 8330, and it still plays most disks just fine). Any suggestions on replacing these DVDs after months or years? The places where I bought them won't replace them after this amount of time. Should I try the original manufacturers? I certainly don't want to buy them all over again. Thanks for any suggestions.