Thanks for the information! I’ll reply inline below:
-“First, a USB device isn’t detected on anything, including the keyboard USB hub. Also not in my Plugable unit.”
Perhaps I still do not fully understand, however, USB devices not being detected through the dock, or the dock itself not being detected as a USB device by the system would be a symptom of the issue I linked to earlier. Though, we usually don’t see USB detection issues unless the system has been rebooted or woken from sleep first.
Has the USB functionality ever worked, or so far nothing you’ve tried has gotten the USB ports to be functional?
-“When I said “findable upon reboot”, I mean that the ability for the Plugable unit to read the video output is not realized. I have to unplug the Mac-source USB-C cable, then plug it back in for my 3 displays to get properly sync’d. I’ve been doing this since I bought the unit.”
Two of the three video outputs (the 2x DP ports) are driven over USB data through the DisplayLink USB graphics chipset in the dock, so USB detection problems would be a high probability for this video behavior. Especially if the issue occurs after a reboot.
I would definitely recommend to try the full shutdown procedure when you have the chance and see if there’s any change.
Also, in case you’re not already doing so please ensure to use the USB-C to USB-C cable the dock shipped with. Sometimes we’ll see a third party C cable be used and that can cause issues as well if the cable isn’t of the same specification.