Code that was being used is commented out, new code is below

header.php.js

/*
        $('#home_testimonials a.wpaudio').bind('click', function() {^M
        if ($(this).hasClass('clicked')) {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_home.png)');^M
          $(this).removeClass('clicked');^M
        } else {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_pause.png)');^M
          $(this).addClass('clicked');^M
        }^M
      });^M
      ^M
      $('#testimonial_columns a.wpaudio').bind('click', function() {^M
        if ($(this).hasClass('clicked')) {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_testimonials.png)');^M
          $(this).removeClass('clicked');^M
        } else {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_pause.png)');^M
          $(this).addClass('clicked');^M
        }^M
      });^M
      ^M
      $('#sidebar_testimonials .listen a.wpaudio').bind('click', function() {^M
        if ($(this).hasClass('clicked')) {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_sidebar.png)');^M
          $(this).removeClass('clicked');^M
        } else {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_pause.png)');^M
          $(this).addClass('clicked');^M
        }^M
      });^M
      ^M
      $('#testimonial_list .testimonial .listen').bind('click', function() {^M
        if ($(this).hasClass('clicked')) {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_testimonials.png)');^M
          $(this).removeClass('clicked');^M
        } else {^M
          $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_pause.png)');^M
          $(this).addClass('clicked');^M
        }^M
      });^M
      */
        $('.wpaudio').click(function() {
            current_image = $(this).css('background-image');
            $('.wpaudio').css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_testimonials.png)');
            if(current_image.match(/icon_pause/)){
                $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_listen_testimonials.png)');
            } else {
                $(this).css('background-image', 'url(<?php bloginfo("template_directory"); ?>/images/icon_pause.png)');
            }
        });