title: Cannot load cached AssetBundle. A file of the same name is already loaded from another AssetBundle
body: <p>I am trying to load a scene but I am getting the error from title and I simply don't know why because I call Unload(false) on AssetBundle. Can someone help me? Thanks.</p>
  
  <pre><code>void Start() {
  ...
   StartCoroutine (DownloadAndCache());
  ...
  }
  
  IEnumerator DownloadAndCache (){
      // Wait for the Caching system to be ready
      while (!Caching.ready)
          yield return null;
  
      // Load the AssetBundle file from Cache if it exists with the same version or download and store it in the cache
          using(WWW www = WWW.LoadFromCacheOrDownload (BundleURL, version)){
              yield return www;
  
              if (www.error != null)
                  throw new Exception("WWW download had an error:" + www.error);
              AssetBundle bundle = www.assetBundle;
  
              bundle.LoadAll();
  
              AsyncOperation async = Application.LoadLevelAsync("main");
              Debug.Log (async.progress);
              yield return async;
  
              bundle.Unload(false);
          }
  }
  </code></pre>