I connect 2 KA7168 with the same firmware version to KH1516AI.  

But 1 port could display 1920x1080 resolution, but the other port could only display 1600x1200 resolution.

How to set to let the KA7168 on the other port to support and display 1920x1080 resolution?

It might be because the EDID stored in KA adapter is incorrect, or it's fixed to certain resolution to cause the problem.

Since KH series doesn't have function in web GUI like KN series to update the EDID information, please follow the steps below to update the EDID information.

1. Connect a monitor which has 1920x1080 resolution to KH1516AI.

2. Power on KH1516AI and login the OSD main.

3. Press [F3] and choose preferred resolution to the resolution selection page.

4. Then choose "monitor default setting" and press Y to change the resolution.

5. If the monitor EDID is captured by KH1516AI correctly, you could go to one of the KVM port to check the display setting of the connected PC.

6. In windows, go to "display setting" and choose "advanced display setting".  You will go the screen like the photo in the attachment.

7. Please check the red mark to see the information is the monitor information like "LED 2271wh"(the model of the monitor we use as an example).

If you see something like "KVM monitor", it means it uses ATEN default EDID, not the monitor's EDID.  

Then please repeat the step 1~4 again and power off the KH1516AI.  After that, power on again.

8. If the EDID is correct, please check another red mark's information, the "desktop mode" and "active signal mode" in advanced display setting.  This is the name in Windows 11.

If you use windows 10, you might see "desktop resolution" and "active signal resolution".

The "desktop mode" or "desktop resolution" is the resolution you set and you want to display, but not exactly the real resolution that PC outputs.

The "active signal mode" or "active signal resolution" is the resolution that PC actually outputs.

Please make sure these 2 resolutions are the same.  Otherwise, the output result will be incorrect resolution.

9. If the 2 resolutions are not the same, please click "Display adapter properties for display".

Then click list all modes to choose the resolution you want to use.  Choose the resolution you want and press "apply" to force PC to use the correct resolution to display.