I have Mac Mini, PC, two external displays and HDMI Matrix.
The problem is that without matrix displays work perfectly with Mac, but if I use matrix to connect them, displays show picture as normal, but after a few seconds they turn black. However if I use Windows Boot Camp on Mac, displays work perfectly without any problem.
Overall
- Displays don't work with macOS on Mac Mini and MacBook Pro using HDMI Matrix (only works for the first few seconds)
- Displays do work when connected directly to Mac (without Matrix)
- Displays do work with PC
- Displays do work with any other OS on Mac Mini or MacBook Pro (Boot Camp Windows/Linux)
Thus it looks like the problem is in macOS, but I don't know how to fix it.
Also, I already tried to reset NRAM, but it didn't help.
Any help will be appreciated!