Hi all. I am new to psychtoolbox and am learning for my experiment. I found that in Mojave system (latest OSX system), PTB always get sync error, even if I skip the 'flip' test (VBL), I can't run through. I tried to go through the PTB files which recommended multiple checks including display card settings. However, in OSX system, I cannot find those set options, seemingly they are OpenGL options. I really need to use PTB in my experiments. Does anyone have any idea about this? I will be really thankful.