I am trying to connect my s90es to my iMac via usb in order to trigger the piano patches on Garageband. I installed the latest driver, set the midi in/out to "usb" and connected the keyboard. The keyboard bed is not triggering sounds from the piano patches, but the other buttons (f1, sf1, track select buttons etc.) are triggering sounds. Also worth noting, I bought the keyboard used so I'm not sure if there's some other special setting I overlooked.