diff --git a/app/js/services.js b/app/js/services.js
index 65fd54f2..77cd672e 100644
--- a/app/js/services.js
+++ b/app/js/services.js
@@ -1491,7 +1491,7 @@ angular.module('myApp.services', [])
     notification.image = notificationPhoto.placeholder;
     notification.key = 'msg' + message.id;
 
-    if (notificationPhoto.location) {
+    if (notificationPhoto.location && !notificationPhoto.location.empty) {
       MtpApiFileManager.downloadSmallFile(notificationPhoto.location, notificationPhoto.size).then(function (url) {
         notification.image = url;
 
diff --git a/server.js b/server.js
index 94a6605c..0df3960d 100755
--- a/server.js
+++ b/server.js
@@ -85,6 +85,7 @@ StaticServlet.MimeMap = {
   'gif': 'image/gif',
   'png': 'image/png',
   'svg': 'image/svg+xml',
+  'wav': 'audio/wav',
   'ico': 'image/vnd.microsoft.icon'
 };