(On a tangent).
Of the older LG drives I've checked out with the older Panasonic chipsets, I've found them to be somewhat smarter at reading problematic dvd discs than LiteOn models. (I don't have any Optiarc designed drives to make a comparison).
For example, various mid-2000s era Universal and Warner released double-sided dvd18 flipper discs with quality control problems, had problems being read on my LiteOn drive. (ie. The Liteon would stop and repeatedly give back a read error at around the transition between layers). But when I ripped these particular problematic flipper discs on an older LG drive with a Panasonic chipset, there were no problems at all. Dvddecrypter didn't spit out any read error messages nor any "pack header not found" messages.
(I haven't tried out enough LG models with a Renesas chipset to determine how good/bad they are at reading problematic discs. But the few which I have tried out, exhibited the "fatal reading behavior" problems on extreme basketcase dvd discs).
Fast forward to the present, these days I would use a current Samsung drive for reading problematic/basketcase dvd discs. For the few extreme baseketcase discs I have which the LiteOn and LG can't read properly at all, it turns out frequently the Samsung can read them fine like a hot knife cutting through butter. Some of these discs I have second copies which didn't have any problems, where the respective md5 and sha* hashes of the corresponding iso rips matched between the basketcase and good error-free dvd copies. It's easier to just buy a second copy for $5 or less, than wasting too much time and effort trying to "salvage" an extremely baseketcase disc. (ie. I only do "salvaging" for research purposes, to check how good/bad a drive is at dealing with extremely basketcase discs).
So if a newly purchased dvd disc can't be ripped properly at with any current Samsung drives, then most likely that particular newly purchased dvd disc is defective.
Today if I encounter a newly purchased dvd disc which can't be ripped at all by a current Samsung drive, I'll just return the disc to the store and do an exchange. Frequently the exchanged new copy doesn't have any problems, unless an entire disc batch is all defective. For example, I've been noticing some 20th Century Fox released multi-disc dvd sets have been declining in disc quality control, where I've had to return/exchange a few Fox tv season sets already.