diff -r 7c1d08cf6956 -r e1baacb52075 src/js/model.js
--- a/src/js/model.js	Fri Sep 14 10:38:04 2012 +0900
+++ b/src/js/model.js	Wed Sep 19 14:11:49 2012 +0900
@@ -364,7 +364,7 @@
         this.contents = new IriSP.Model.List(this.source.directory);
         this.contents.addIds(this.id);
     } else {
-        this.contents = this.source.directory.getElement(this.id);
+        this.contents = this.source.getElement(this.id);
     }
     
 }
@@ -450,6 +450,23 @@
 
 IriSP.Model.Media.prototype = new IriSP.Model.Element();
 
+/* Default functions to be overriden by players */
+
+IriSP.Model.Media.prototype.getCurrentTime = function() {  return new IriSP.Model.Time(0); }
+
+IriSP.Model.Media.prototype.getVolume = function() { return .5; }
+
+IriSP.Model.Media.prototype.getPaused = function() { return true; }
+
+IriSP.Model.Media.prototype.getMuted = function() { return false; }
+
+IriSP.Model.Media.prototype.setCurrentTime
+    = IriSP.Model.Media.prototype.setVolume
+    = IriSP.Model.Media.prototype.setMuted
+    = IriSP.Model.Media.prototype.play
+    = IriSP.Model.Media.prototype.pause
+    = function() {}
+    
 IriSP.Model.Media.prototype.setDuration = function(_durationMs) {
     this.duration.setMilliseconds(_durationMs);
 }
@@ -647,6 +664,23 @@
     }
 }
 
+/* Default functions to be overriden by players */
+
+IriSP.Model.Mashup.prototype.getCurrentTime = function() { return new IriSP.Model.Time(0); }
+
+IriSP.Model.Mashup.prototype.getVolume = function() { return .5; }
+
+IriSP.Model.Mashup.prototype.getPaused = function() { return true; }
+
+IriSP.Model.Mashup.prototype.getMuted = function() { return false; }
+
+IriSP.Model.Mashup.prototype.setCurrentTime
+    = IriSP.Model.Mashup.prototype.setVolume
+    = IriSP.Model.Mashup.prototype.setMuted
+    = IriSP.Model.Mashup.prototype.play
+    = IriSP.Model.Mashup.prototype.pause
+    = function() {}
+
 /* */
 
 IriSP.Model.Source = function(_config) {
@@ -768,6 +802,23 @@
     }
 }
 
+IriSP.Model.Source.prototype.getCurrentMedia = function(_opts) {
+    if (typeof this.currentMedia === "undefined") {
+        if (_opts.is_mashup) {
+            var _mashups = this.getMashups();
+            if (_mashups.length) {
+                this.currentMedia = _mashups[0];
+            }
+        } else {
+            var _medias = this.getMedias();
+            if (_medias.length) {
+                _media = _medias[0];
+            }
+        }
+    }
+    return this.currentMedia;
+}
+
 IriSP.Model.Source.prototype.merge = function(_source) {
     var _this = this;
     _source.forEach(function(_value, _key) {