diff --git a/tools/aviocat.c b/tools/aviocat.c
index c43c69d1be..183cdf70dd 100644
--- a/tools/aviocat.c
+++ b/tools/aviocat.c
@@ -89,6 +89,7 @@ int main(int argc, char **argv)
         }
     }
 
+    avio_flush(output);
     avio_close(output);
 fail:
     avio_close(input);