www.makemkv.com

I've been using MakeMKV on Mac OSX for years, but it has got really slow since I upgraded to 1.15.1.

Ripping a UHD movie now seems to take about 2 hours, compared to about 30 minutes on the older version.

I'm using the same drive and nothing else has changed. The rip speed seems to top out a 3.2x now, compared to 6.0x before and the drive constantly spins down and then up again during the course of a rip.

I don't seem to get any errors, everything works fine, but is just very slow.

Where are you writing to? I had a slowdown a few weeks back, with lots of "Program reads faster than it can write" errors, and LONG pauses at the end of each video. That was when only one ripping stream was active.

Tracked it down to a bad cable between the network switch and the media server, damaged when someone threw stuff at my server rack. Replaced the cable, and all the speed returned, being able to maintain at least 3 ripping streams with no delays.

To test if it is 1.15.1, you can go to https://makemkv.com/download/old/ and pull one of the older versions to compare with.

I just upgraded to 1.15.1 and have very slow read speeds (~0.6x) when backing up Blu-Rays. I downgraded to 1.14.7 and am back up and running as usual. Not sure what could have changed between releases, but it seems something is up with 1.15.1.

Creating an MKV from backed-up files doesn't seem to be any slower. It's still very fast when reading from HDD.