External screen with different refresh rate over DP over USB-C

Hi everyone.

I just tried the newest and greatest Manjaro 21 release (KDE) and wanted to get my setup working.

Unfortunately, I don’t manage to use my external monitor with 144hz. Not even when I disable my internal monitor (60hz). I tried both; X11 and Wayland.

When I enable 144hz, the screen kind of goes black on the right half and starts flickering like crazy; switching back to 60hz fixes these issues.

The thing is: I’m running a 4700u notebook (envy x360) with a USB-C-Dock (HP Dock G5) that pushes the screen-signal (DP) over USB-C. All components use the newest firmware versions.

I also tried the newest stable kernel; without success.
I also tried to enable 144hz using xrandr; without success.

Can anyone tell me, how I get this working properly? It’s important to get 144hz on my main screen as I’m using Moonlight to stream games (144hz) from my Windows machine.

Any help is highly appreciated.

Best

qdrop