I am encountering very bad problem using Sierra + xcode 8 + iOS Simulator: I develop midi application, but now , when I start the iOS Simulator I get no midi-port available, I mean: Usualle using Studio Midi is possible to see the virtual iOS device, plus you can see se the session, typically named Session 1. being this is possible to re-route the MidiNetwork ( midi_driver ) to a physical port, but now, using Sierra the iOS Simulator is not visible no longer, and I do not know ( and where to find ) a solution. Very bad situation because it stopped the developing and code-production. Any Good idea to solve this????