M2 Mac Mini with LG 4K Monitor on Thunderbolt port Backlight stays on
I have the M2 Mac Mini and I connected an LG UltraFine External monitor to it.
The monitor has a built in USB hub so I have connected it to the Mac via Thunderbolt/USB-C cable for display and to utilize the USB hub.
I have my screen set to enter the screensaver mode after 5 minutes and then to turn off the monitor after 10 minutes and I also set it so that the Mac does not automatically sleep when the monitor is off.
I noticed that after 10 minutes, when the monitor is supposed to shut off, the backlight of the monitor remains on.
I switched to an HDMI cable and everything works as expected, the monitor will shut off after 10 minutes and the backlight does not stay on.
Furthermore, another monitor which is exactly the same and it is connected via Thunderbolt/USB-C to my 14 inch M1 MacBook Pro (my work computer) and this issue does not occur.
I have swapped monitors to see if one may be bad, but it is not an issue with the monitors.
The issue only seems to be when the monitor is connected to my Mac M2 Mini on the Thunderbolt 4 port.
I have tried multiple settings configurations and multiple Thunderbolt cables but nothing seems to resolve the issue.
As it currently stands, I have to turn off my monitor at night or if I'm going to be away for a lengthy time.
I would prefer to use the Thunderbolt cable so that I have use of the USB Hub in the monitor and also because when I try using an HDMI cable it only give me a 30 hz refresh rate which I do not like.
If anyone has any suggestions on how to resolve this, I would greatly appreciate it.
To make matters worse, it seems somewhat intermittent. Mostly its like this, but sometimes it works as it should.
Mac mini (M2, 2023)