First, my configuration, I have a 2017 4 port USB-c Mac Pro currently running catalina but the same used to occur at least in the later Mojave release. The MAC is connected to an elgato dock and the Dock connected to a HDMI splitter then to a LG 4k monitor. The other side of the splitter is connected to my windows machine. ie. MAC shares the monitor with the windows machine.
My problem is that the splitter has autosensing and that the Mac, when apparently asleep, sems to poll for the monitor every so often. Some times it takes 15 minutes and other times 2 minutes. The MAC continues to poll no matter what and even though it is asleep. (it is dead stone cold so definitely asleep). When the MAC polls the splitter switches over to the MAC. This behaviour never happened on High Sierra. I do know that Mojave had a lot of issues at the end with external monitors and i ended up working with Apple to diagnose a 10.14.6 issue where the DisplayServer goes high CPU if you enable nightshift when it attempts to shift. Mojave would continously try and change resolution every 1 ms or so. Only answer to that was upgrade to Catalina. The same polling problem started in the later releases of Mojave.
Does anyone know why the Mac would poll monitors while asleep? I suspect this is a left over from Mojave and whatever went wrong in the supplementary updates. Any help appreciated.
My problem is that the splitter has autosensing and that the Mac, when apparently asleep, sems to poll for the monitor every so often. Some times it takes 15 minutes and other times 2 minutes. The MAC continues to poll no matter what and even though it is asleep. (it is dead stone cold so definitely asleep). When the MAC polls the splitter switches over to the MAC. This behaviour never happened on High Sierra. I do know that Mojave had a lot of issues at the end with external monitors and i ended up working with Apple to diagnose a 10.14.6 issue where the DisplayServer goes high CPU if you enable nightshift when it attempts to shift. Mojave would continously try and change resolution every 1 ms or so. Only answer to that was upgrade to Catalina. The same polling problem started in the later releases of Mojave.
Does anyone know why the Mac would poll monitors while asleep? I suspect this is a left over from Mojave and whatever went wrong in the supplementary updates. Any help appreciated.