All,
After struggling with my LG Drive (LG WH16NS40 flashed to 1.02MK), and having numerous theories as to why mine was making a HORRID grinding noise, I finally figured out why the noise was happening, which was causing it also to stop reading many discs.
A Small Ribbon Cable inside of the drive is about a quarter-inch too long and was interfering with the laser sled.
To fix this, take the drive apart (I followed this guide: https://www.youtube.com/watch?v=3cNFGK2GF0E, yes it's an old video, and yes, the disassembly process is essentially identical to a 20 year-old drive), and I scotch-taped the smaller ribbon cable to the adjacent larger ribbon cable to get it out of the way of the laser sled. It has since been working flawlessly on discs it previously wouldn't read.
I would recommend against pulling it taut, but rather just getting the cable out of the way as you don't want the cable pulling against the clasp connectors, which you would need soldering skills to fix.
Hopefully this topic finds someone out there and fixes their issues as well.
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M2TS Error
M2TS corrupt or invalid
The source file '/BDMV/STREAM/00000.m2ts' is corrupt or invalid at offset XXXXXXXX, attempting to work around