HP 27F through a KVM (4K,60Hz)

[MarkS6i]

I have an HP 27F monitor that I have successfully used on both my Windows 10 Asus and MacBook Pro as an extended monitor through an HDMI cable.  I just bought a KVM (4K@60Hz) so that I could, with a press of a button, switch my keyboard, mouse and external monitors (the other is a Dell 24") between them.  Everything works except for the HP 27F when connected through the KVM.  I have tested all the cabling by switching the cables through all combinations with the Dell, which always works, and also works if I connect the HP 27F directly with those same cables to either laptop.

When connected through the KVM, I get an endless cycle of 'Input Signal Not Found', 'Check the video cable and video source's and 'Display going to sleep' (which it never does, since it immediate brings up another dialog with those messages).  If I unplug that very same cable and plug it into the Dell, it works as expected.  So it isn't the case that the cabling is bad or generically the video signal.  I am assuming that the HP 27F is looking for something on the HDMI signal that it gets when connected directly to the laptop(s) that it doesn't get from the KVM.  Does anyone have any idea on how to solve this issue?

[MarkS6i · Accepted solution]

Finally got it to work.  I reset my OSD menu (power button for 20+ seconds) and then when I changed input to HDMI 1 (where the cable was connected), it worked.  The strange thing was that the OSD menu was already unlocked (I was able to switch inputs before).  Hopefully no further issues.  If it continues to go well, I will definitely replace the Dell monitor (borrowed from my office) with another HP 27F, which, all things considered, I like better!