Have JavaScript send returned values to two inputs elements

I am trying to add a section of code (shown below) to have my audio book picker supply an audio file name, as well as displaying the chapter and chapter number.

How can I make my added code send the second set of returned values to the input field with the id='audio', just as it sends return values to the input with the id='chapter-picker'?

var chapterPicker = myApp.picker({
      input: '#chapter-picker',
      rotateEffect: true,
      formatValue: function (picker, values) {
          return values[0] + ' ' + values[1];
      }, 

      //Start of what I am trying to add
      input: '#audio',
      rotateEffect: true,
      formatValue: function (picker, values) {
          return values[0] + values[1] + '.mp3';
      }
      //End of what I am trying to add 

      cols: [
          {
              textAlign: 'left',
              values: ['Genesis', 'Exodus', 'Leviticus'],
              onChange: function (picker, book) {
                  if(picker.cols[1].replaceValues){
                      picker.cols[1].replaceValues(chapters[book]);
                  }
              }
          },
          {
              values: chapters.Genesis,
              width: 160,
          },
      ]
  });