4K at 60Hz didn't work. However, 4K @30Hz works. The problem at 30Hz is that the mouse movement is very jerky and my expensive monitor feels cheap. It works fine at resolutions lower than 4K. Resetting the keyboard [Ctrl-Ctrl-R] doesn't work either, but the keyboard shortcuts to switch screens [Alt-Ctrl-1 or Alt-Ctrl-2] work fine. However, when my computers wake up from sleep, the keyboard and mouse are not recognized. I have to disconnect and reconnect the USB. It seems to be some kind of hardware race condition.
TESmart 1080P 60Hz USB VGA KVM Extender Over Cat5e Cat6 Ethernet Cable - Long Range 984ft/300m (Sender+Receiver)
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π HDMI 2.0 4 Port KVM Switch with 4K@60Hz, 2K@144Hz,1080P@120Hz Support, 18Gbps Bandwidth, USB 2.0 Keyboard/Mouse/Printer/Monitor/PC Selector, Audio Out/Mic In, HDR10, Dolby Vision, Dolby/DTS, HDCP2.2 Compatibility
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4 Port USB 3.0 Switch Selector - Pubioh KVM Switch for Mouse, Keyboard, Printer, Scanner - 2 in 4 Out Sharing Box with Switch Button and 2 USB 3.0 A to A Cables
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π TRENDnet TK-803R: 8-Port Rack Mount KVM Switch with VGA & USB Connection, USB/PS2 Support, Device Monitoring, Auto Scan - Control 8 Computers/Servers
10 Review