By Andrew Mee in collaboration with the OS API Working Group. This is the second part of a series demonstrating how a developer may go about building a USB MIDI 2.0 device. You should read Part 1 before this Part 2. Part 1 is here: https://www.midi.org/midi-articles/building-a-usb-midi-2-0-device-part-1 In the last part we created a simple set of U...