diff --git a/sample-midi-piano/README.md b/sample-midi-piano/README.md
index ecd098a..00981bb 100644
--- a/sample-midi-piano/README.md
+++ b/sample-midi-piano/README.md
@@ -6,7 +6,9 @@
 `npm install`
 
 ## Run
-`electron .`
+`electron .`  
+or  
+`npm start`
 
 ## Package
 `npm run make`
diff --git a/sample-midi-player/README.md b/sample-midi-player/README.md
index 43cf3b5..87b9874 100644
--- a/sample-midi-player/README.md
+++ b/sample-midi-player/README.md
@@ -6,7 +6,9 @@
 `npm install`
 
 ## Run
-`electron .`
+`electron .`  
+or  
+`npm start`
 
 ## Package
 `npm run make`
diff --git a/sample-midi-player/index.js b/sample-midi-player/index.js
index 808ce9c..20a4b33 100644
--- a/sample-midi-player/index.js
+++ b/sample-midi-player/index.js
@@ -39,7 +39,7 @@ function createWindow () {
 function openFile() {
   dialog.showOpenDialog({
     properties: ['openFile'],
-    filters: [{ name: 'MIDI Files', extensions: ['mid', 'midi', 'kar', 'rmi'] }, { name: 'All Files', extensions: ['*'] }]
+    filters: [{ name: 'MIDI Files', extensions: ['mid', 'midi', 'midi2', 'kar', 'rmi'] }, { name: 'All Files', extensions: ['*'] }]
   }).then(function(result) {
     if (result.filePaths && result.filePaths[0]) {
       fs.readFile(result.filePaths[0], 'binary', (err, data) => {