Testing with https://python.microbit.org/v/beta
Editor Version: 2.2.0-beta.5;
MicroPython Version: 1.0.1/2.0.0-beta.5
An error occurs if music.play specifies pin=None, either directly or through a variable.
import microbit
from microbit import *
import music
myPin=pin0
while True:
music.play(music.JUMP_UP)
sleep(1000)
music.play(music.JUMP_UP,pin=myPin)
sleep(1000)
myPin=None