Thats a fair point, and I didn't mean to make it sound like the A port doesn't work with any MIDI pedal. So let me restate, I found with the Morningstar MC6 pro the player USB B port seems to work perfectly, whereas when I tested the player with the Morningstar MC6pro using the A port I had less reliable results. BTW I love this pedal. I used it on stage today and it worked flawlessly. I uploaded rigs from my Profiler rack and was astounded with how the player assumed all the settings. I A B the player to the rack unit and could not tell them apart. The player is a game changer.