I have been having intermittent problems ever since receiving the hub when I got my mac it had MacOS Sierra, and everytime I wanted to use an external monitor (Which I do every day) I have to remove the HDMI and re-insert which 9 times out of 10 would get it working Since updating to MacOS High Sierra this has completely stopped working . I have a wired connection which is detected and I plug in my charger into the dock which also charges the Mac. But no HDMI I pressume this is a driver issue of which I cannot find for High Sierra. Anyone else had this and know how to fix it please?!