A significant minority of the discs I put in the external CD-ROM thingy vibrate exceedingly loudly and start moving. I have to put a heavy thing beside it so it doesn’t vibrate to the edge of the cabinet and fall off. Honestly, it sounds like a garden strimmer while spinning. These disks take longer to rip. Perhaps the problem is something to do with the way the data is structured. MakeMKV sometimes whines about there being tens of thousands of VOBUs and structure protection. Don’t know how a VOBU differs from a VOB.