Alumium Cinema Display loses USB on reboot

[pierrox]

I have a 20" Cinema Display - the silver aluminium model - which is hooked to a Mac Pro 5,1 running a RX 580 GPU using DVi (or DisplayPort via an adapter). I hadn't used it in a while since I have a 23" too, but with the confinement measures here in Europe, I'm now working from home - hence the smaller 20".
After a day of use, I noticed the USB ports of the display would stop working in some cases. Did various tests - unplugging/replugging the USB that goes to the monitor makes it work again - and I ended up realising that the USB ports always work on fresh boot. In other words, when I boot in the morning, all fine. Now if I reboot the Mac, the USB ports on the monitor stop working and I have to unplug/replug to get them back. Or I can shut the Mac down, wait a second, and restart it with its power button.
Is it a known problem? Is there some kind of reset that can be done on the monitor?

 

[D_Hanson54]

I'm having a similar problem after installing the RX580; no audio, mic, or camera connection but other USB devices function normally. Did you ever find a solution?

 

[pierrox]

Never. It must be my monitor as when I went back to my office after lockdown and switched to my 23" Cinema Displays and the issue went away.

 

[pierrox]

Continuing on my own thread: when I go to System Preferences and set the button of my Apple Display to "Puts the computer to sleep or wakes it", the setting won't stick. It works once and when I wake the computer or restart it, it defaults back to "Does nothing".
Any idea? (Mojave and Mac Pro 2010)