KVM switch shortcut does not work on USB-B downstream computer

Hi,

I have issue with KVM functionality on S3423DWC and U2722DE monitors. I can switch from computer connected to  USB-C port, but cannot switch back to it if using keyboard attached to a monitor downstream USB port.To switch back I need to use keyboard on a laptop, attached to a USB-C port or use monitor menu, which is clumsy and defies intended  KVM functionality. Keyboard and mouse itself are working fine via both monitors. There is disappearing USB headphone sound issue though.

I have tried to assign custom shortcut on a USB-C computer, it changes and properly switches to another input both using input and computer switch shortcuts. On a USB-B computer if I press default Alt+P shortcut nothing happens, if I press AL+I, I do get a .NET error, index out of range. DDM .NET error

I cannot change default shortcut on a computer, connected via USB-B downstream port, as DDM shows NO KVM functionality on S3423DWC and as far as I remember on U2722DE. To be fair DDM on second computer shows almost NO functionality as I can only adjust window layout (which I do not use). Other settings are inactive or completely missing (like KVM).

The setup on S3423DWC is as follows:

• Dell Latitude 5320 connected via USB-C
• HP Elitebook 850 G5 connected via upstream USB-B and HDMI2

The setup on U2722DE is as follows:

• Dell Latitude 5320 connected via USB-C
• HP Elitebook 850 G5 connected via upstream USB-B and HDMI
• Desktop PC connected via DP port and uses own keyboard and mouse.

HDMI is properly assigned to USB upstream ports on both monitors. I have tried to enable AutoKVM in monitor and  it did not help.

DDM is updated to latest 2.1.1.36. Firmware is reported as latest on both monitors. Any ideas how to switch back from HP laptop?