4 USB 2.0 ports on the front do not work. I've bought 2 of these and tried 3 different brands of mouse/keyboard from reputable companies with no luck.
CKL Quad Monitor HDMI KVM Switch 4 Port 4K@30Hz with Cables - Extended and Mirrored Display Support for Windows, Linux, and Mac
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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
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Enhance Productivity with CKL HDMI KVM 2 Port 4K 30Hz Dual Monitor Extended Display (CKL-922HUA)
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