I think I may have found a defective movie dvd disc from my collection, which can give some definitive answers about how “sick” the fatal reading behavior is of this LG GH24NSC0 drive.
The dvd disk in question is a poorly manufactured dvd9 double-layer disc which has no css encryption. For some technical specs from dvddecrypter, this disc has sectors:
LBA: 0 - 4012431
where the first layer covers LBA: 0 - 2065711 and the second layer covers LBA: 2065712 - 4012431.
The bad sectors appear to be around the transition between the two layers. These files of interest in this section are:
VTS_03_0.IFO - (LBA: 1130056 - 1130082)
VTS_03_0.VOB - (LBA: 1130083 - 1130139)
VTS_03_1.VOB - (LBA: 1130140 - 1654341)
VTS_03_2.VOB - (LBA: 1654342 - 2065684)
VTS_03_0.BUP - (LBA: 2065685 - 2065711)
VTS_04_0.IFO - (LBA: 2065712 - 2065748)
On the LG GH24NSC0 drive, it cannot read VTS_04_0.IFO at all. (ie. It is buried under the bad sectors). But the VTS_03 files are readable.
(I later ran isopuzzle on this disc with the LG drive, and it indeed stops in its tracks when it reaches LBA 2065712).
The fatal reading behavior of this LG drive shows up when I get dvddecrypter to read VTS_03_2.VOB - (LBA: 1654342 - 2065684). I read VTS_03_2.VOB five different times, where the error messages indicated junk data being read in different batches of sectors. No two times did the exact same sectors coincide with junk data. It was as if the LG was pumping out garbage data on the fly if it couldn’t immediately read an mpeg2 data sector properly. Calculating md5 hashes on these five different copies of VTS_03_2.VOB I made, showed that they were indeed different.
(Using my LiteOn and Samsung drives to copy VTS_03_2.VOB with dvddecrypter, there were no error messages about garbage data sectors. Hashes on these LiteOn and Samsung rips of VTS_03_2.VOB showed that they were the same files).
I then got dvddecrypter to copy the VTS_03_0.IFO and VTS_03_0.BUP files ten times with the LG drive. A few times the LG drive stuttered for a few seconds when attempting to read the VTS_03_0.BUP file. Calculating hashes for all these copies of VTS_03_0.IFO and VTS_03_0.BUP, showed that they were indeed all the same. (As they should be). I even looked at each of these ifo and bup files on a text editor, just too see whether they showed the same pattern of ascii characters, for which they did.
These anecdotal observations suggests that the fatal reading behavior of the LG GH24NSC0 drive, appears to be primarily affecting sectors which correspond to mpeg2 packets (ie. vob files). Non-mpeg2 sectors might possibly not be affected by this fatal reading behavior.
I don’t know how exactly this LG GH24NSC0 drive distinguishes between mpeg2 and non-mpeg2 sectors, especially in the case of unreadable bad sectors. If I had to guess, there might be a table somewhere on a dvd disc which tells you which sector ranges are mpeg2 and which ones are not ?