[junkgear]

Unfortunately, the Korg microKey keyboards do not have an external jack for connecting a sustain pedal, which is what you would do with the NP-2.

The NP-2 is basically a switch and would normally plug into your keyboard, which would trigger sustain when pressed. The keyboard would then send the MIDI command for sustain out the MIDI port, where it would get recorded by Pro Tools. Even though it is the same size jack, you can not and should not connect the NP-2 to your audio interface.

First, I would take the NP-2 back to the store where you got it from since you can not use it with the microKey.

If you do want to play around with sustain, just to see how it would work in Pro Tools, you can try the following:

Install the Korg Editor software that came with your Korg microKey. After connecting your microKey, edit the Modulation Wheel CC number from CC1 to CC64. This will allow you to sustain your keys by moving the Modulation Wheel. You will not have Modulation Effect when the CC number is 64.