4 layers

Kvm base
thatoddmailbox/kvm-base
The main board for the open-source HDMI KVM switch I built.
70 parts19
Boards in 2 GitHub repositories, designed in KiCad, that use the FSUSB74UMX by onsemi (-40℃~+85℃ 2.5V~4.4V 9Ω UFQFN-16(1.8x2.6) Analog Switches, Multiplexers ROHS). See how each wires it, with its parts, size, README and files; the FSUSB74UMX’s symbol, footprint and pinout are on its own page.

thatoddmailbox/kvm-base
The main board for the open-source HDMI KVM switch I built.

StarweaverAudioLabs/main_control_board
Main controller board for Haruto's DAC