diff --git a/Assets/Scenes/SandboxMain.cs b/Assets/Scenes/SandboxMain.cs
index 201a91b..1faf82d 100644
--- a/Assets/Scenes/SandboxMain.cs
+++ b/Assets/Scenes/SandboxMain.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.IO;
 using System.Threading;
 using UniRx.Async;
 using UnityEngine;
@@ -15,19 +16,11 @@ public class SandboxMain : MonoBehaviour
 
     async void Start()
     {
-        await UniTask.CompletedTask;  // ok
+        UnityEngine.Debug.Log("DOWNLOAD START:" + Time.frameCount);
 
-        // var subject = new Subject<Unit>();
-        //subject.OnCompleted();
-        IObservable<AsyncUnit> subject = default;
-        try
-        {
-            await subject.ToUniTask();  // exception
-        }
-        catch (Exception exception)
-        {
-            Debug.Log(exception);
-        }
+        var req = await UnityWebRequest.Get(Path.Combine(Application.streamingAssetsPath, "test.txt")).SendWebRequest();
+
+        UnityEngine.Debug.Log("DOWNLOAD RESULT:" + Time.frameCount + ", " + req.downloadHandler.text);
     }
 }
 
diff --git a/Assets/StreamingAssets.meta b/Assets/StreamingAssets.meta
new file mode 100644
index 0000000..4d1953d
--- /dev/null
+++ b/Assets/StreamingAssets.meta
@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 7bb6ff9f1f0d0cd4da5ba7623f10dd6b
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/Assets/StreamingAssets/test.txt b/Assets/StreamingAssets/test.txt
new file mode 100644
index 0000000..e6fe8fd
--- /dev/null
+++ b/Assets/StreamingAssets/test.txt
@@ -0,0 +1 @@
+MyTEST
\ No newline at end of file
diff --git a/Assets/StreamingAssets/test.txt.meta b/Assets/StreamingAssets/test.txt.meta
new file mode 100644
index 0000000..dc3dcc7
--- /dev/null
+++ b/Assets/StreamingAssets/test.txt.meta
@@ -0,0 +1,7 @@
+fileFormatVersion: 2
+guid: 7fc83f79aef22a2449d5e9ca4964b2e0
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: