www.makemkv.com

I have a USB Blu-ray drive , when I insert a disk an start MakeMkv, it reads the disc and displays the contents. However , if I press the eject button on the disc drive and insert a new disc, MakeMkv appears to scan it but keeps the previous disc's information on the screen.

A work around is to close MakeMkv and re-open it. It will scan the disc and display the correct information.

OS: MacOS High Sierra 10.13.5 (17F77)
Drive: Pioneer Electronics USA Slim External Blu Ray Drive BDR-XD05S Silver
MakeMkv: 1.12.2

MacOS is caching the information and returning it when MakeMKV asks, rather than properly sensing (and reporting) the disk change. Exiting MakeMKV forced MacOS to discard the cache information, but the real fix is getting the operating system to sense that the disk has changed.

(if it makes you feel any better, Windows does this quite often, too)