Include MIDI to a Android RC car.

I’m having problems with the insertion of a MIDI song along with my engine controls.
I want to merge both codes into one, and link a button in RoboRemo to activate and deactivate the MIDI song.
I’m trying to merge them, but I simpy can’t… sometimes it doesn’t even compile.
I’d appreciate any help on my code as I’m doing it for a school project.
(and sorry, my first contact with this forum)

rc.ino (1.86 KB)

darth.ino (3.63 KB)