function musicOff() {
document.midi.stop()
}

function musicOn() {
document.midi.play()
}

function changeButton() {
//if (document.onoff.B1.value=='Turn music off') {
//document.onoff.B1.value='Turn music on';
//musicOff()
//}
//else {
//document.onoff.B1.value='Turn music off';
musicOff()
  //}
}