diff --git a/libusb/os/darwin_usb.c b/libusb/os/darwin_usb.c
index 7202337..6de8102 100644
--- a/libusb/os/darwin_usb.c
+++ b/libusb/os/darwin_usb.c
@@ -1131,10 +1131,13 @@
     usbi_localize_device_descriptor(&dev->device_descriptor);
     dev->session_data = cached_device->session;
 
+    if (NULL != dev->parent_dev) {
+      libusb_unref_device(dev->parent_dev);
+      dev->parent_dev = NULL;
+    }
+
     if (cached_device->parent_session > 0) {
       dev->parent_dev = usbi_get_device_by_session_id (ctx, (unsigned long) cached_device->parent_session);
-    } else {
-      dev->parent_dev = NULL;
     }
 
     (*(priv->dev->device))->GetDeviceSpeed (priv->dev->device, &devSpeed);
diff --git a/libusb/version_nano.h b/libusb/version_nano.h
index f375044..1f2431b 100644
--- a/libusb/version_nano.h
+++ b/libusb/version_nano.h
@@ -1 +1 @@
-#define LIBUSB_NANO 11629
+#define LIBUSB_NANO 11630