Review on TRENDnet 2-Port Dual Monitor DisplayPort KVM Switch with Audio, 2-Port USB 2.0 Hub, 4K UHD Resolutions up to 3840 x 2160 - TK-240DP (Renewed) by Marlo Schlachter

As another reviewer noted, this doesn't support PC connections during swaps. I have two identical HP laptops in docking stations and two identical HP 24 inch monitors. Switching from PC 1 to PC 2 requires a 12 second wait for the monitors to turn off and on again. When they do that, the windows are rearranged where I left them. Go from PC2 to PC1, wait 12 seconds, then the monitors are not recognized, so I have to turn off the monitor, wait 4 seconds, then turn it back on - this wakes everything up and the desktop is rearranged. Combined with the nasty double beeps when changing the PC and the fact that the thing comes without a cable, this is a bad purchase. Look elsewhere.