Save Google Voice Voicemails to Google Drive

save_vm.js

/* Originally Written by Amit Agarwal amit@labnol.org   */
/* Tutorial: http://www.labnol.org/?p=25153  */
/* Edited by David Pollack */
/* https://gist.github.com/dhpollack/0f47db0d238db166405f */
function savevm() {
  
  var folder,  folder_name = "vms";
  var gmail_label  = "gv";
  var archive_label = "gv/processed"; 
  
  /* Find Google Voice messages in Gmail */
  
  var filter  = "label:" + gmail_label + " -label:" + archive_label;    
  var threads = GmailApp.search(filter, 0, 5);
  
  if (threads.length) {
    
    /* Google Drive folder where the MP3 files will get stored */
    var folders = DriveApp.getFoldersByName(folder_name); 
    folder = folders.hasNext() ? folders.next() : DriveApp.createFolder(folder_name);
    
    /* Gmail Label that is applied to processed voice mails */
    var archive = GmailApp.getUserLabelByName(archive_label) ? 
      GmailApp.getUserLabelByName(archive_label) : GmailApp.createLabel(archive_label);
    
    for (var x=0; x<threads.length; x++) {
      
      threads[x].addLabel(archive);
      
      var msg = threads[x].getMessages()[0];
      
      /* Find the link to play the voice mail message */
      var url = msg.getBody().match(/https?:\/\/www.google.com\/voice\/fm[^\"]*/gi);
      
      if (url) {
        
        /* Find the name of the voice sender (or their phone number) */
        var file_name = msg.getSubject().match(/new voicemail from (.*) at /i);
        
        /* Add the voice mail date to the file name */
        var file_date = Utilities.formatDate(
          msg.getDate(), Session.getScriptTimeZone(), "yyyy-MM-dd HH:mm");
        
        var file_save_name = file_date + " - " + file_name[1] + ".mp3";
        
        if (file_name && !DriveApp.getFilesByName(file_save_name).hasNext()) {
          
          /* Extract the audio file and save as an MP3 file */
          var mp3 = url[0].replace("/voice/fm/", "/voice/media/svm/");
          var file = folder.createFile(UrlFetchApp.fetch(mp3).getBlob());
          
          /* Save the voice mail transcript with the audio file */
          file.setName(file_save_name);
          file.setDescription(msg.getPlainBody());
          
        }                   
      }        
    }      
  }
}

This doesn't seem to work anymore... specifically, the trick of looking at "media/svm" just returns an empty file whereas it used to return the voice file.