MacBook Pro 2019 along with the Apple USB-C AV adapter support 60Hz refresh rate. But when I connect them to my Space 32, I get a refresh rate of only 30Hz at 3840x2160 resolution. The option that allows you to change the refresh rate in display preferences is grayed out and stuck at 30Hz. The firmware of my monitor as well as the OS (Mojave - 10.14.6) are up-to-date. Is there some setting that I have overlooked? Or is there a compatibility issue between these monitors and MacBook Pros?