Sure, I don't blame you when your controller is so close to the Sd40 all the time, but It sounded like you had an issue with some kind of a Bluetooth MIDI receiver when you said, "I was going to try the microkey air but the sd40 didn't recognise the midi Bluetooth adapter." Obviously you were not using any kind of a Bluetooth MIDI receiver. I wanted to clarify it for musicians with other controllers such as MIDI guitar, midi accordion, or wind controller that the SD40 will work just fine with the USB Bluetooth MIDI receiver I mentioned.

Besides some MIDI accordions, I have a MIDI guitar that sends MIDI over Bluetooth. The same company is coming out with a MIDI guitar with a 5 pin DIN MIDI out. With the right tool, all these controllers will talk to the SD40 fitted with a Bluetooth MIDI receiver.

Chris