diff --git a/libraries/PID/PID.cpp b/libraries/PID/PID.cpp
index 4fe529256f..330e950049 100644
--- a/libraries/PID/PID.cpp
+++ b/libraries/PID/PID.cpp
@@ -21,7 +21,7 @@ PID::get_pid(long error, long dt, float scaler)
 		// discrete low pass filter, cuts out the 
 		// high frequency noise that can drive the controller crazy
 		derivative = _last_derivative + 
-			((delta_time / (RC + delta_time)) * (derivative - _last_derivative));
+			((delta_time / (_RC + delta_time)) * (derivative - _last_derivative));
 
 		// update state
 		_last_error 		= error;
diff --git a/libraries/PID/PID.h b/libraries/PID/PID.h
index 8ccf949885..82298c9d03 100644
--- a/libraries/PID/PID.h
+++ b/libraries/PID/PID.h
@@ -67,14 +67,15 @@ public:
 
 	/// @name	parameter accessors
 	//@{
-	float	 kP()	{ return _kp; }
-	float	&kP()	{ return _kp; }
-	float	 kI()	{ return _ki; }
-	float	&kI()	{ return _kd; }
-	float	 kD()	{ return _kd; }
-	float	&kD()	{ return _kd; }
-	float	 imax()	{ return _imax; }
-	float	&imax()	{ return _imax; }
+	float	kP()			{ return _kp; }
+	float	kI()			{ return _ki; }
+	float	kD()			{ return _kd; }
+	float	imax()			{ return _imax; }
+
+	void	kP(float v)		{ _kp = v; }
+	void	kI(float v)		{ _ki = v; }
+	void	kD(float v)		{ _kd = v; }
+	void	imax(float v)	{ _imax = v; }
 	//@}
 
 private: