This is my first post.
I don’t know if anybody else has noticed this, but I have noticed some recent LG drives seem to be reading garbage data (or blanks) on some movie dvd discs with css encryption. I base this on recently using an internal GH24NSC0 drive, and an external GP50NB40 drive (with a December 2013 manufacturing date).
(For a bit of background).
I’m primarily into collecting/watching movies (and tv shows) on dvd and bluray. I have very little to no interest in the burning capabilities of optical drives.
Over the years I’ve made the mistake of buying too many movie dvds and not watching them immediately. Though once I got around to watching these movie dvd discs, it turned out several had random bad sectors from manufacturing defects. (Deliberate bad sectors due to basketcase drm is an entirely different thing, which I won’t go into here).
These days I found it was easier to just find another dvd copy of the same movie in the local bargain bins, than trying to “salvage” the old defective discs. But with that being said, I’ve kept the defective discs largely to use them as “torture tests” on various dvd drives and players. It turns out not every dvd drive/player is created equally, in regard to reading capabilities. For quite a few of these defective discs, I’ve found that the reading behaviors may be quite different on LiteOn, LG, and Samsung computer dvd drives. (Recent Samsung drives seem to be the smartest at dealing with random bad sectors, which the LiteOn may choke on).
In regard to recent LG drives I’ve tried out, it turns out for several basketcase movie dvd discs I have with random bad sectors, the LG drive just returns junk data where the bad sectors are. On dvddecrypter, the debug logs indicated that the mpeg2 headers are missing from these particular sectors. (On a LiteOn drive reading the same bad sectors, the LiteOn just stops there and repeatedly gives back a read error).
For these same movie discs where I later purchased a second identical copy of the disc, these second copies didn’t have any read errors and had all the proper mpeg2 headers. Dvddecrypter didn’t spit out any error messages when reading these second copies. So my first copies were definitely defective. (These were largely widely released mass market dvd movies, that were available almost everywhere like BestBuy, WalMart, etc …).
In the end, I ended up returning the GH24NSC0 to the store, and purchased a recent ASUS dvd drive instead.