diff --git a/hardware/arduino/cores/arduino/Tone.cpp b/hardware/arduino/cores/arduino/Tone.cpp
index e221ecfa5..3ea034bf9 100755
--- a/hardware/arduino/cores/arduino/Tone.cpp
+++ b/hardware/arduino/cores/arduino/Tone.cpp
@@ -33,8 +33,8 @@ Version Modified By Date     Comments
 
 #include <avr/interrupt.h>
 #include <avr/pgmspace.h>
-#include <wiring.h>
-#include <pins_arduino.h>
+#include "wiring.h"
+#include "pins_arduino.h"
 
 #if defined(__AVR_ATmega8__)
 #define TCCR2A TCCR2