Scanning a DVD hangs, but only on some discs in a box set

[WhensDinner]

I have a box set of Death Note, it's 9 DVD9 discs. I was able to rip the first disc no issues. However, disc 2 causes the scanning process to stall. The program is still responsive, but there's no progress being made. The log reads:

Using direct disc access mode
Title #1 has length of 22 seconds which is less than minimum title length of 120 seconds and was therefore skipped
Title #2 was added (21 cell(s), 1:31:05)
Title #3 was added (6 cell(s), 0:22:46)
Title #4 was added (21 cell(s), 1:31:05)
Title #5 was added (2 cell(s), 0:10:10)
Title #6 has length of 23 seconds which is less than minimum title length of 120 seconds and was therefore skipped
Title #7 has length of 50 seconds which is less than minimum title length of 120 seconds and was therefore skipped
Title #8 has length of 47 seconds which is less than minimum title length of 120 seconds and was therefore skipped
Title #9 has length of 97 seconds which is less than minimum title length of 120 seconds and was therefore skipped
Title #10 was added (3 cell(s), 0:03:07)
Title #04 in VTS 2 is equal to title #02 and was skipped

And it will sit there forever. It's hung on "Decrypting data". It says it's on Titleset id: VTS_2 and CSS sectors scanned: 5

Now, what's odd is that if I try to rip once, then copy the files to my computer and open the files instead of the disc, it works. It does pause in the same spot as before, but only for maybe 5 seconds or so. Dumping the video works normally as well.

The DVDs are region 4. The drive is originally region 1, but I changed it to 4 in case that was the issue. It hung in the same spot when the drive was region 1, just with a few lines of "DVD region of disc and drive won't match, attempting workaround..." in the log as well. This is the only out of region set of discs I'll likely ever see, so I figure no matter what I'll just change it back when this resolves.

I've tried all of the different CellWalk/Trim/Full methods, it all ends the same way.

Edit: I eventually managed to rip the discs by waiting for it to stall for a decent amount of time (like 10 minutes) and then canceling the scan. It would then show me an incomplete list of titles, but the main title was always in there, so I just muscled through the box set that way. Still no idea why it stopped.