diff --git a/common/rateest.cpp b/common/rateest.cpp
index 98afe53..e64c980 100644
--- a/common/rateest.cpp
+++ b/common/rateest.cpp
@@ -19,25 +19,35 @@
 #include "rateest.h"
 #include <cstdlib>
 
-void RateEst::init(const long srate) {
-	this->srate.est = srate;
-	this->srate.var = srate >> 13;
+static long limit(long est, const long reference) {
+	if (est > reference + (reference >> 4))
+		est = reference + (reference >> 4);
+	else if (est < reference - (reference >> 4))
+		est = reference - (reference >> 4);
+	
+	return est;
+}
+
+void RateEst::init(long srate, const long reference) {
+	this->srate.est = limit(srate, reference);
+	this->srate.var = srate >> 12;
 	last = 0;
+	this->reference = reference;
 	samples = 0;
-	count = 16;
+	count = 32;
 }
 
 void RateEst::feed(const long samplesIn) {
 	samples += samplesIn;
 		
 	if (--count == 0) {
-		count = 16;
+		count = 32;
 		
 		const usec_t now = getusecs();
 		
 		if (last) {
 			long est = samples * 1000000.0f / (now - last) + 0.5f;
-			est = (srate.est * 15 + est + 8) >> 4;
+			est = limit((srate.est * 31 + est + 16) >> 5, reference);
 			srate.var = (srate.var * 15 + std::abs(est - srate.est) + 8) >> 4;
 			srate.est = est;
 		}
diff --git a/common/rateest.h b/common/rateest.h
index 646ca86..dad95aa 100644
--- a/common/rateest.h
+++ b/common/rateest.h
@@ -31,12 +31,15 @@ public:
 private:
 	Result srate;
 	usec_t last;
+	long reference;
 	long samples;
 	unsigned count;
 	
 public:
-	RateEst(const long srate=0) { init(srate); }
-	void init(long srate);
+	RateEst(long srate = 0) { init(srate); }
+	RateEst(long srate, long reference) { init(srate, reference); }
+	void init(long srate) { init(srate, srate); }
+	void init(long srate, long reference);
 	void feed(long samples);
 	const Result& result() const { return srate; }
 };
diff --git a/gambatte_qt/src/audioengines/alsaengine.cpp b/gambatte_qt/src/audioengines/alsaengine.cpp
index a5a9113..0485213 100644
--- a/gambatte_qt/src/audioengines/alsaengine.cpp
+++ b/gambatte_qt/src/audioengines/alsaengine.cpp
@@ -150,7 +150,7 @@ int AlsaEngine::write(void *const buffer, const unsigned samples) {
 	}
 	
 	if (underrun)
-		est.init(std::min(est.result().est + (est.result().est >> 10), (long) rate() + (rate() >> 4)));
+		est.init(est.result().est + (est.result().est >> 10), rate());
 	
 	return 0;
 }
diff --git a/gambatte_qt/src/audioengines/ossengine.cpp b/gambatte_qt/src/audioengines/ossengine.cpp
index b44e0e1..c162d7a 100644
--- a/gambatte_qt/src/audioengines/ossengine.cpp
+++ b/gambatte_qt/src/audioengines/ossengine.cpp
@@ -124,7 +124,7 @@ int OssEngine::write(void *const buffer, const unsigned samples) {
 		if (bstate.fromUnderrun)
 			est.feed(prevfur - bstate.fromUnderrun);
 		else
-			est.init(std::min(est.result().est + (est.result().est >> 10), (long) rate() + (rate() >> 4)));
+			est.init(est.result().est + (est.result().est >> 10), rate());
 	}
 	
 	prevfur = bstate.fromUnderrun + samples;
diff --git a/gambatte_qt/src/blitterwidget.cpp b/gambatte_qt/src/blitterwidget.cpp
index 3ddf1d1..60fe535 100644
--- a/gambatte_qt/src/blitterwidget.cpp
+++ b/gambatte_qt/src/blitterwidget.cpp
@@ -36,7 +36,7 @@ void FtEst::update(const usec_t t) {
 		if (--count == 0) {
 			count = COUNT;
 			long oldFtAvg = ftAvg;
-			ftAvg = (ftAvg * 15 + ft + 8) >> 4;
+			ftAvg = (ftAvg * 31 + ft + 16) >> 5;
 			
 			if (ftAvg > ((frameTime + (frameTime >> 5)) << COUNT_LOG2))
 				ftAvg = (frameTime + (frameTime >> 5)) << COUNT_LOG2;
diff --git a/gambatte_qt/src/blitterwidget.h b/gambatte_qt/src/blitterwidget.h
index b3717bd..e8b477e 100644
--- a/gambatte_qt/src/blitterwidget.h
+++ b/gambatte_qt/src/blitterwidget.h
@@ -28,7 +28,7 @@
 class QHBoxLayout;
 
 class FtEst {
-	enum { COUNT_LOG2 = 4 };
+	enum { COUNT_LOG2 = 5 };
 	enum { COUNT = 1 << COUNT_LOG2 };
 	
 	long frameTime;