diff --git a/src/generic/usb_cdc.c b/src/generic/usb_cdc.c
index 07b38d0e..96bd01c6 100644
--- a/src/generic/usb_cdc.c
+++ b/src/generic/usb_cdc.c
@@ -475,6 +475,7 @@ void
 usb_shutdown(void)
 {
     usb_notify_bulk_in();
+    usb_notify_bulk_out();
     usb_notify_ep0();
 }
 DECL_SHUTDOWN(usb_shutdown);