diff --git a/action.php b/action.php
index 3b071bc68..aa983b78d 100644
--- a/action.php
+++ b/action.php
@@ -221,8 +221,12 @@ if (ini_get('safe_mode') == 0)
   @set_time_limit(0);
 }
 // Without clean and flush there may be some image download problems, or image can be corrupted after download
-ob_clean();
-flush();
+if (ob_get_length() !== FALSE)
+{
+  ob_clean();
+  flush();
+}
+
 @readfile($file);
 
 ?>