ATEM mini Pro - only Input 1 shows image (20m ethernet)

Hi I have an interesting situation with my Atem Mini Pro.
1. All my 4 ports work with 5m HDMI cables
2. I am testing 20m ethernet cable plugged in with hdmi/ethernet adapters
3. I am plugging the adapter to input 1 - image works perfectly.
4. I am pluggin the same cable and adapter to input 2, 3 and 4 - no image.
5. I am changing the hdmi source - from DSLR camera to action cam - the exact same behavior is observed on the same ports - hdmi 1 shows clear picture, the other ports don't show anything.
Conclusion - the ports handle the same hdmi signal differently.
I updated my firmware 2 weeks ago to the latest one.
How this can be remediated so I can show signal on all the 4 inputs with 20m ethernet?
Thanks in advance!
1. All my 4 ports work with 5m HDMI cables
2. I am testing 20m ethernet cable plugged in with hdmi/ethernet adapters
3. I am plugging the adapter to input 1 - image works perfectly.
4. I am pluggin the same cable and adapter to input 2, 3 and 4 - no image.
5. I am changing the hdmi source - from DSLR camera to action cam - the exact same behavior is observed on the same ports - hdmi 1 shows clear picture, the other ports don't show anything.
Conclusion - the ports handle the same hdmi signal differently.
I updated my firmware 2 weeks ago to the latest one.
How this can be remediated so I can show signal on all the 4 inputs with 20m ethernet?
Thanks in advance!