diff --git a/app/src/main/java/com/danielkim/soundrecorder/RecordingService.java b/app/src/main/java/com/danielkim/soundrecorder/RecordingService.java
index 5aa935a6..339e5f61 100644
--- a/app/src/main/java/com/danielkim/soundrecorder/RecordingService.java
+++ b/app/src/main/java/com/danielkim/soundrecorder/RecordingService.java
@@ -84,6 +84,7 @@ public void startRecording() {
         mRecorder.setOutputFormat(MediaRecorder.OutputFormat.MPEG_4);
         mRecorder.setOutputFile(mFilePath);
         mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AAC);
+        mRecorder.setAudioChannels(1);
 
         try {
             mRecorder.prepare();