Ok.. So I have had this "bug" migrate into my Logic system a few months ago and had time today to trouble shoot. My AKAI S-5000 that is patched into MIDI port 1 on my Unitor 8 plays as expected when the sequencer is NOT running. When the sequencer plays I can hardly get a note to sound from the AKAI? It seems to be dropping out our going out different ports I've recreated this with my startup template or a fresh new session. Is their a way to trash MIDI prefrences?