title: Android Oreo notification keep making Sound even if I do not set sound. On Older version, works perfectly
body: <p>So I am making my app compatible with Oreo and facing issue with notification.</p>
  
  <p>I added notification channel according to documentation and everything is working smooth except notification keep making sound on every posting, tried setting defaults to 0 as well.</p>
  
  <p>I am testing my app in emulator, any help is highly appreciated.</p>
  
  <p>Used this code for creating channel</p>
  
  <pre><code>  NotificationCompat.Builder builder = new NotificationCompat.Builder(PlayerService.this, "channel_01")
                              .setAutoCancel(false)
                              .setContentIntent(pendingIntent)
                              .setContent(viewsSmall)
                              .setCustomBigContentView(viewsExpanded)
                              .setDeleteIntent(pSwipeToDismiss);
  
              if (Build.VERSION.SDK_INT &gt;= Build.VERSION_CODES.LOLLIPOP) {
                  builder.setVisibility(Notification.VISIBILITY_PUBLIC);
              }
  
              if (Build.VERSION.SDK_INT &gt; Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1) {
                  builder.setPriority(Notification.PRIORITY_MAX);
              }
  
  
              if (Build.VERSION.SDK_INT &gt;= Build.VERSION_CODES.O) {
                              /* Create or update. */
                  NotificationChannel channel = new NotificationChannel("channel_01",
                              "Playback Notification",
                              NotificationManager.IMPORTANCE_DEFAULT);
                      mNotificationManager.createNotificationChannel(channel);
                      mBuilder.setChannelId("channel_01");
                  }
      final Notification notification = builder.build();
  
                      startForeground(Constants.NOTIFICATION_ID.FOREGROUND_SERVICE,notification);
  </code></pre>