I have a function run when a link is clicked in a grid. The function worked fine until i added two ux items. Since I'm sure the ux.grid.Search and the ux.MediaWindow is probably fine, I am guessing i have something messed up. I used the examples from the message box demo to show a wait message, start an ajax call and then based on the response, showan alert or change the window location. It stopped working and started throwing the error: "a.getItemId is not a function"

Here is the function. I have it outside of the onReady but am completely stumped. I have narrowed it down tothe message boxes.... meaning if I comment those lines out, it works.
Any thoughts on a glaring mistake?

Code:
function gwnld(id,vidt,act,h){
    var action;
    var linkd;
    var msgb;
    Ext.MessageBox.show({
       msg: 'Starting your download...',
       progressText: 'Saving...',
       title:'Download',
       width:300,
       wait:true,
       waitConfig: {interval:200},
       icon:'ext-mb-download'
   });
    Ext.Ajax.request({
       url: 'myurl.php',
       success: function(result, request){
           var jsonData = Ext.util.JSON.decode(result.responseText);
           switch(jsonData.action){
               case 'max':
                    Ext.Msg.alert('Download Error','my error message');
                    break;
                case 'rate':
                    Ext.Msg.alert('Rating Alert','rate message');
                    break;
               case 'redir':
                    Ext.Msg.alert('Download Error','An unhandled exception has occured.  An email has been generated to the site admin.');
                    break;
               case 'down':
                    window.location.assign(jsonData.link);
                    Ext.MessageBox.hide();
                    break;
               default:
                    Ext.Msg.alert('Download Error','An unhandled exception has occured.  An email has been generated to the site admin.');
               }

       },
       failure: function(){
           Ext.Msg.alert('Download Error','An unhandled exception has occured.  An email has been generated to the site admin.');
           Ext.MessageBox.hide();
       }
    });
   
}