CC-3429: Firefox does not natively support mp3 file playing so preview does nothing.

- removed useless logging in AudiopreviewController.php.
- updated if statement syntax in audio-preview.phtml according to review comments.

airtime_mvc/application/controllers/AudiopreviewController.php

@@ -152,8 +152,6 @@ class AudiopreviewController extends Zend_Controller_Action
      */
     public function getShowAction()
     {
-        Logging::log("in audio previews getShowAction");
-
         // disable the view and the layout
         $this->view->layout()->disableLayout();
         $this->_helper->viewRenderer->setNoRender(true);