jPlayer javascript in Rails layout is causing Routing Error

I'm trying to use jPlayer to play an mp3. I have the jPlayer CSS and images working, now it's just a matter of playing the mp3. To do so, I include the following javascript in the application.html.erb layout's head:

  <script type="text/javascript">
  $(document).ready(function(){
    $("#jquery_jplayer_1").jPlayer({
      ready: function () {
        $(this).jPlayer("setMedia", {
             mp3: "media/sound.mp3",
          // m4a: "http://www.jplayer.org/audio/m4a/Miaow-07-Bubble.m4a",
          // oga: "http://www.jplayer.org/audio/ogg/Miaow-07-Bubble.ogg"
        });
      },
      swfPath: "/javascripts",
      supplied: "mp3, m4a, oga"
    });
  });

When I load the page and click the play button, I get the following routing error:

ActionController::RoutingError (No route matches [GET] "/calls/media/sound.mp3")

Would someone mind taking a spare minute to explain to me why this is? Should I be including the javascript in something like this?

<%= javascript_tag 'some js code' %>

Any assistance is very much appreciated. Thanks in advance.

Solution

I realized I was I was missing a starting / i.e. changed "media/sound.mp3" to "/media/sound.mp3".

Then, I decided to use a path helper