diff --git a/FM.cpp b/FM.cpp
index ad8b5f5..074de3d 100644
--- a/FM.cpp
+++ b/FM.cpp
@@ -41,7 +41,8 @@ m_filterStage2(32768,      0,-32768, 32768, -50339, 19052),
 m_filterStage3(32768, -65536, 32768, 32768, -64075, 31460),
 m_blanking(),
 m_useCOS(true),
-m_rxBoost(1U)
+m_rxBoost(1U),
+m_rxLevel(128 * 128)
 {
 }
 
@@ -144,10 +145,11 @@ uint8_t CFM::setAck(const char* rfAck, uint8_t speed, uint16_t frequency, uint8_
   return m_rfAck.setParams(rfAck, speed, frequency, level, level);
 }
 
-uint8_t CFM::setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, bool useCOS, uint8_t rxBoost, uint8_t maxDev)
+uint8_t CFM::setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, bool useCOS, uint8_t rxBoost, uint8_t maxDev, uint8_t rxLevel)
 {
   m_useCOS  = useCOS;
   m_rxBoost = q15_t(rxBoost);
+  m_rxLevel = q15_t(rxLevel * 128);
 
   m_timeoutTimer.setTimeout(timeout, 0U);
   m_kerchunkTimer.setTimeout(kerchunkTime, 0U);
@@ -401,13 +403,14 @@ void CFM::beginRelaying()
 q15_t CFM::getUnscaledSample(q15_t sample)
 {
   // sample / rxLevel
-  q15_t rxLevel = io.getRxLevel();
   q31_t sample31 = q31_t(sample) << 16;
-  if (((sample31 >> 31) & 1) == ((rxLevel >> 15) & 1))
-    sample31 += rxLevel >> 1;
+
+  if (((sample31 >> 31) & 1) == ((m_rxLevel >> 15) & 1))
+    sample31 += m_rxLevel >> 1;
   else
-    sample31 -= rxLevel >> 1;
-  sample31 /= rxLevel;
+    sample31 -= m_rxLevel >> 1;
+
+  sample31 /= m_rxLevel;
 
   return q15_t(sample31);
 }
diff --git a/FM.h b/FM.h
index f2190d7..1a07eb8 100644
--- a/FM.h
+++ b/FM.h
@@ -54,7 +54,7 @@ public:
 
   uint8_t setCallsign(const char* callsign, uint8_t speed, uint16_t frequency, uint8_t time, uint8_t holdoff, uint8_t highLevel, uint8_t lowLevel, bool callsignAtStart, bool callsignAtEnd);
   uint8_t setAck(const char* rfAck, uint8_t speed, uint16_t frequency, uint8_t minTime, uint16_t delay, uint8_t level);
-  uint8_t setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, bool useCOS, uint8_t rxBoost, uint8_t maxDev);
+  uint8_t setMisc(uint16_t timeout, uint8_t timeoutLevel, uint8_t ctcssFrequency, uint8_t ctcssThreshold, uint8_t ctcssLevel, uint8_t kerchunkTime, uint8_t hangTime, bool useCOS, uint8_t rxBoost, uint8_t maxDev, uint8_t rxLevel);
 
 private:
   CFMKeyer             m_callsign;
@@ -78,6 +78,7 @@ private:
   CFMBlanking          m_blanking;
   bool                 m_useCOS;
   q15_t                m_rxBoost;
+  q15_t                m_rxLevel;
 
   void stateMachine(bool validSignal, uint8_t length);
   void listeningState(bool validSignal);
diff --git a/IO.cpp b/IO.cpp
index afd56b0..a737693 100644
--- a/IO.cpp
+++ b/IO.cpp
@@ -592,8 +592,3 @@ bool CIO::hasLockout() const
 {
   return m_lockout;
 }
-
-q15_t CIO::getRxLevel() const
-{
-  return m_rxLevel;
-}
diff --git a/IO.h b/IO.h
index f3ac4f9..07ed700 100644
--- a/IO.h
+++ b/IO.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -56,8 +56,6 @@ public:
   
   void selfTest();
 
-  q15_t getRxLevel() const;
-
 private:
   bool                 m_started;
 
diff --git a/SerialPort.cpp b/SerialPort.cpp
index f729cb3..7a6e609 100644
--- a/SerialPort.cpp
+++ b/SerialPort.cpp
@@ -408,7 +408,7 @@ uint8_t CSerialPort::setFMParams2(const uint8_t* data, uint8_t length)
 
 uint8_t CSerialPort::setFMParams3(const uint8_t* data, uint8_t length)
 {
-  if (length < 10U)
+  if (length < 11U)
     return 4U;
 
   uint16_t timeout        = data[0U] * 5U;
@@ -425,8 +425,9 @@ uint8_t CSerialPort::setFMParams3(const uint8_t* data, uint8_t length)
 
   uint8_t  rxBoost        = data[8U];
   uint8_t  maxDev         = data[9U];
+  uint8_t  rxLevel        = data[10U];
 
-  return fm.setMisc(timeout, timeoutLevel, ctcssFrequency, ctcssThreshold, ctcssLevel, kerchunkTime, hangTime, useCOS, rxBoost, maxDev);
+  return fm.setMisc(timeout, timeoutLevel, ctcssFrequency, ctcssThreshold, ctcssLevel, kerchunkTime, hangTime, useCOS, rxBoost, maxDev, rxLevel);
 }
 
 uint8_t CSerialPort::setMode(const uint8_t* data, uint8_t length)