diff --git a/Makefile b/Makefile
index f8d7885b..21bf3cfe 100644
--- a/Makefile
+++ b/Makefile
@@ -197,7 +197,7 @@ UNF ?= 0
 $(eval $(call validate-option,UNF,0 1))
 ifeq ($(UNF),1)
   DEFINES += UNF=1
-  SRC_DIRS += src/usbOfast
+  SRC_DIRS += src/usb
   USE_DEBUG := 1
 endif