I have plugged an M-Audio Keystation 61es into my Macbook pro. Mainstage (and Garageband) recognize the keyboard but all the notes are a semi tone up. For example, when I hit the C1 key on the Keyboard, the software recognizes and plays C#1. Any solutions?
For anyone interested, I solved my own problem. At some point the keyboard had be transposed. To solve this you press the advanced function key and then the F#3 Key. The exact function of these advanced function keys are found in the M-Audio keystation manual!