My Dell laptop is connected to the M28U with type-c to Type-c cable, but the keyboard/mouse won't work.
Speakers work.
The keyboard/mouse work on my desktop that uses Display Port cable (2.1) and the USB-B cable to the desktop Type-A USB 3.1 (Red) port also.
I'm not sure what is going on?
I installed M28U monitor driver and sidekick. but still no mouse keyboard to Type-C to Type-C of my laptop.