diff --git a/audio-mixer/src/AvatarAudioRingBuffer.cpp b/audio-mixer/src/AvatarAudioRingBuffer.cpp
index 243e91033e..61d23f0fe6 100644
--- a/audio-mixer/src/AvatarAudioRingBuffer.cpp
+++ b/audio-mixer/src/AvatarAudioRingBuffer.cpp
@@ -6,9 +6,13 @@
 //  Copyright (c) 2013 HighFidelity, Inc. All rights reserved.
 //
 
+#include <PacketHeaders.h>
+
 #include "AvatarAudioRingBuffer.h"
 
-AvatarAudioRingBuffer::AvatarAudioRingBuffer() : _freeVerbs() {
+AvatarAudioRingBuffer::AvatarAudioRingBuffer() :
+    _freeVerbs(),
+    _shouldLoopbackForAgent(false) {
     
 }
 
@@ -17,4 +21,9 @@ AvatarAudioRingBuffer::~AvatarAudioRingBuffer() {
     for (FreeVerbAgentMap::iterator verbIterator = _freeVerbs.begin(); verbIterator != _freeVerbs.end(); verbIterator++) {
         delete verbIterator->second;
     }
+}
+
+int AvatarAudioRingBuffer::parseData(unsigned char* sourceBuffer, int numBytes) {
+    _shouldLoopbackForAgent = (sourceBuffer[0] == PACKET_HEADER_MICROPHONE_AUDIO_WITH_ECHO);
+    return PositionalAudioRingBuffer::parseData(sourceBuffer, numBytes);
 }
\ No newline at end of file
diff --git a/audio-mixer/src/AvatarAudioRingBuffer.h b/audio-mixer/src/AvatarAudioRingBuffer.h
index 779f642f5a..1ca069b70c 100644
--- a/audio-mixer/src/AvatarAudioRingBuffer.h
+++ b/audio-mixer/src/AvatarAudioRingBuffer.h
@@ -21,13 +21,17 @@ public:
     AvatarAudioRingBuffer();
     ~AvatarAudioRingBuffer();
     
+    int parseData(unsigned char* sourceBuffer, int numBytes);
+    
     FreeVerbAgentMap& getFreeVerbs() { return _freeVerbs; }
+    bool shouldLoopbackForAgent() const { return _shouldLoopbackForAgent; }
 private:
     // disallow copying of AvatarAudioRingBuffer objects
     AvatarAudioRingBuffer(const AvatarAudioRingBuffer&);
     AvatarAudioRingBuffer& operator= (const AvatarAudioRingBuffer&);
     
     FreeVerbAgentMap _freeVerbs;
+    bool _shouldLoopbackForAgent;
 };
 
 #endif /* defined(__hifi__AvatarAudioRingBuffer__) */
diff --git a/audio-mixer/src/InjectedAudioRingBuffer.cpp b/audio-mixer/src/InjectedAudioRingBuffer.cpp
index b866c2650e..bb890caeb1 100644
--- a/audio-mixer/src/InjectedAudioRingBuffer.cpp
+++ b/audio-mixer/src/InjectedAudioRingBuffer.cpp
@@ -6,6 +6,8 @@
 //  Copyright (c) 2013 HighFidelity, Inc. All rights reserved.
 //
 
+#include <cstring>
+
 #include <PacketHeaders.h>
 
 #include "InjectedAudioRingBuffer.h"
diff --git a/audio-mixer/src/PositionalAudioRingBuffer.cpp b/audio-mixer/src/PositionalAudioRingBuffer.cpp
index 81911fc9df..a518e1534c 100644
--- a/audio-mixer/src/PositionalAudioRingBuffer.cpp
+++ b/audio-mixer/src/PositionalAudioRingBuffer.cpp
@@ -6,6 +6,8 @@
 //  Copyright (c) 2013 HighFidelity, Inc. All rights reserved.
 //
 
+#include <cstring>
+
 #include <PacketHeaders.h>
 
 #include "PositionalAudioRingBuffer.h"
@@ -14,7 +16,6 @@ PositionalAudioRingBuffer::PositionalAudioRingBuffer() :
     AudioRingBuffer(false),
     _position(0.0f, 0.0f, 0.0f),
     _orientation(0.0f, 0.0f, 0.0f, 0.0f),
-    _shouldLoopbackForAgent(false),
     _willBeAddedToMix(false)
 {
     
diff --git a/audio-mixer/src/PositionalAudioRingBuffer.h b/audio-mixer/src/PositionalAudioRingBuffer.h
index d1752fa0bf..41e775e74a 100644
--- a/audio-mixer/src/PositionalAudioRingBuffer.h
+++ b/audio-mixer/src/PositionalAudioRingBuffer.h
@@ -28,8 +28,6 @@ public:
     const glm::vec3& getPosition() const { return _position; }
     const glm::quat& getOrientation() const { return _orientation; }
     
-    bool shouldLoopbackForAgent() const { return _shouldLoopbackForAgent; }
-    
 protected:
     // disallow copying of PositionalAudioRingBuffer objects
     PositionalAudioRingBuffer(const PositionalAudioRingBuffer&);
@@ -37,7 +35,6 @@ protected:
     
     glm::vec3 _position;
     glm::quat _orientation;
-    bool _shouldLoopbackForAgent;
     bool _willBeAddedToMix;
 };
 
diff --git a/audio-mixer/src/main.cpp b/audio-mixer/src/main.cpp
index ac3c1ade6f..d84a995767 100644
--- a/audio-mixer/src/main.cpp
+++ b/audio-mixer/src/main.cpp
@@ -324,7 +324,8 @@ int main(int argc, const char* argv[]) {
         
         // pull any new audio data from agents off of the network stack
         while (agentList->getAgentSocket()->receive(agentAddress, packetData, &receivedBytes)) {
-            if (packetData[0] == PACKET_HEADER_MICROPHONE_AUDIO) {
+            if (packetData[0] == PACKET_HEADER_MICROPHONE_AUDIO_NO_ECHO ||
+                packetData[0] == PACKET_HEADER_MICROPHONE_AUDIO_WITH_ECHO) {
                 Agent* avatarAgent = agentList->addOrUpdateAgent(agentAddress,
                                                                  agentAddress,
                                                                  AGENT_TYPE_AVATAR,
diff --git a/interface/src/Application.cpp b/interface/src/Application.cpp
index 95457403b4..c85e8ecd96 100644
--- a/interface/src/Application.cpp
+++ b/interface/src/Application.cpp
@@ -19,6 +19,7 @@
 #endif
 
 #include <glm/gtx/quaternion.hpp>
+#include <glm/gtx/vector_angle.hpp>
 
 #include <QActionGroup>
 #include <QBoxLayout>
@@ -303,11 +304,12 @@ void Application::paintGL() {
     } else if (OculusManager::isConnected()) {
         _myCamera.setUpShift       (0.0f);
         _myCamera.setDistance      (0.0f);
-        _myCamera.setTightness     (100.0f);
+        _myCamera.setTightness     (0.0f);     //  Camera is directly connected to head without smoothing
         _myCamera.setTargetPosition(_myAvatar.getHeadJointPosition());
         _myCamera.setTargetRotation(_myAvatar.getHead().getOrientation());
     
     } else if (_myCamera.getMode() == CAMERA_MODE_FIRST_PERSON) {
+        _myCamera.setTightness(0.0f);  //  In first person, camera follows head exactly without delay
         _myCamera.setTargetPosition(_myAvatar.getBallPosition(AVATAR_JOINT_HEAD_BASE));
         _myCamera.setTargetRotation(_myAvatar.getHead().getWorldAlignedOrientation());
         
@@ -316,19 +318,9 @@ void Application::paintGL() {
         _myCamera.setTargetRotation(_myAvatar.getHead().getWorldAlignedOrientation());
     }
     
-    // important...
+    // Update camera position
     _myCamera.update( 1.f/_fps );
     
-    // Render anything (like HUD items) that we want to be in 3D but not in worldspace
-    /*
-    const float HUD_Z_OFFSET = -5.f;
-    glPushMatrix();
-    glm::vec3 test(0.5, 0.5, 0.5);
-    glTranslatef(1, 1, HUD_Z_OFFSET);
-    drawVector(&test);
-    glPopMatrix();
-     */
-    
     
     // Note: whichCamera is used to pick between the normal camera myCamera for our 
     // main camera, vs, an alternate camera. The alternate camera we support right now
@@ -1567,6 +1559,7 @@ void Application::init() {
 
 void Application::updateAvatar(float deltaTime) {
 
+    
     if (_serialHeadSensor.active) {
       
         // Update avatar head translation
@@ -1600,7 +1593,6 @@ void Application::updateAvatar(float deltaTime) {
 
     }
 
-    
     if (OculusManager::isConnected()) {
         float yaw, pitch, roll;
         OculusManager::getEulerAngles(yaw, pitch, roll);
@@ -1609,7 +1601,7 @@ void Application::updateAvatar(float deltaTime) {
         _myAvatar.getHead().setPitch(pitch);
         _myAvatar.getHead().setRoll(roll);
     }
-    
+     
     //  Get audio loudness data from audio input device
     #ifndef _WIN32
         _myAvatar.getHead().setAudioLoudness(_audio.getLastInputLoudness());
@@ -1971,7 +1963,7 @@ void Application::displaySide(Camera& whichCamera) {
             }
         }
         agentList->unlock();
-            
+        
         // Render my own Avatar 
         _myAvatar.render(_lookingInMirror->isChecked(), _renderAvatarBalls->isChecked());
         _myAvatar.setDisplayingLookatVectors(_renderLookatOn->isChecked());
diff --git a/interface/src/Audio.cpp b/interface/src/Audio.cpp
index 954d1df528..cba5139c05 100644
--- a/interface/src/Audio.cpp
+++ b/interface/src/Audio.cpp
@@ -135,7 +135,9 @@ int audioCallback (const void* inputBuffer,
             // + 12 for 3 floats for position + float for bearing + 1 attenuation byte
             unsigned char dataPacket[BUFFER_LENGTH_BYTES_PER_CHANNEL + leadingBytes];
             
-            dataPacket[0] = PACKET_HEADER_MICROPHONE_AUDIO;
+            dataPacket[0] = (Application::getInstance()->shouldEchoAudio())
+                ? PACKET_HEADER_MICROPHONE_AUDIO_WITH_ECHO
+                : PACKET_HEADER_MICROPHONE_AUDIO_NO_ECHO;
             unsigned char *currentPacketPtr = dataPacket + 1;
             
             // memcpy the three float positions
diff --git a/interface/src/Avatar.cpp b/interface/src/Avatar.cpp
index 0e8d0114b6..76831605b4 100644
--- a/interface/src/Avatar.cpp
+++ b/interface/src/Avatar.cpp
@@ -7,6 +7,7 @@
 
 #include <glm/glm.hpp>
 #include <glm/gtx/quaternion.hpp>
+#include <glm/gtx/vector_angle.hpp>
 #include <vector>
 #include <lodepng.h>
 #include <SharedUtil.h>
@@ -87,9 +88,9 @@ _worldUpDirection(DEFAULT_UP_DIRECTION),
 _mouseRayOrigin(0.0f, 0.0f, 0.0f),
 _mouseRayDirection(0.0f, 0.0f, 0.0f),
 _interactingOther(NULL),
-_cumulativeMouseYaw(0.0f),
 _isMouseTurningRight(false),
 _voxels(this)
+
 {
     
     // give the pointer to our head to inherited _headData variable from AvatarData
@@ -279,16 +280,12 @@ void Avatar::updateHeadFromGyros(float deltaTime, SerialInterface* serialInterfa
     const float AMPLIFY_PITCH = 2.f;
     const float AMPLIFY_YAW = 2.f;
     const float AMPLIFY_ROLL = 2.f;
-    
-    float measuredPitchRate = serialInterface->getLastPitchRate();
-    float measuredYawRate = serialInterface->getLastYawRate();
-    float measuredRollRate = serialInterface->getLastRollRate();
-    
-    //  Update avatar head position based on measured gyro rates
-    _head.addPitch(measuredPitchRate * AMPLIFY_PITCH * deltaTime);
-    _head.addYaw(measuredYawRate * AMPLIFY_YAW * deltaTime);
-    _head.addRoll(measuredRollRate * AMPLIFY_ROLL * deltaTime);
-    
+
+    glm::vec3 estimatedRotation = serialInterface->getEstimatedRotation();
+    _head.setPitch(estimatedRotation.x * AMPLIFY_PITCH);
+    _head.setYaw(estimatedRotation.y * AMPLIFY_YAW);
+    _head.setRoll(estimatedRotation.z * AMPLIFY_ROLL);
+        
     //  Update head lean distance based on accelerometer data
     glm::vec3 headRotationRates(_head.getPitch(), _head.getYaw(), _head.getRoll());
     
@@ -321,11 +318,10 @@ glm::quat Avatar::getWorldAlignedOrientation () const {
 }
 
 void  Avatar::updateFromMouse(int mouseX, int mouseY, int screenWidth, int screenHeight) {
-    //  Update yaw based on mouse behavior
+    //  Update head yaw and pitch based on mouse input
     const float MOUSE_MOVE_RADIUS = 0.15f;
-    const float MOUSE_ROTATE_SPEED = 3.0f;
+    const float MOUSE_ROTATE_SPEED = 4.0f;
     const float MOUSE_PITCH_SPEED = 1.5f;
-    const float MAX_YAW_TO_ADD = 180.f;
     const int TITLE_BAR_HEIGHT = 46;
     float mouseLocationX = (float)mouseX / (float)screenWidth - 0.5f;
     float mouseLocationY = (float)mouseY / (float)screenHeight - 0.5f;
@@ -334,30 +330,18 @@ void  Avatar::updateFromMouse(int mouseX, int mouseY, int screenWidth, int scree
         //
         //  Mouse must be inside screen (not at edge) and not on title bar for movement to happen
         //
-        if (fabs(mouseLocationX) > MOUSE_MOVE_RADIUS) {
-            //  Add Yaw
-            float mouseYawAdd = (fabs(mouseLocationX) - MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_ROTATE_SPEED;
-            bool rightTurning = (mouseLocationX > 0.f);
-            if (_isMouseTurningRight == rightTurning) {
-                _cumulativeMouseYaw += mouseYawAdd;
-            } else {
-                _cumulativeMouseYaw = 0;
-                _isMouseTurningRight = rightTurning;
-            }
-            if (_cumulativeMouseYaw < MAX_YAW_TO_ADD) {
-                setBodyYaw(getBodyYaw() - (rightTurning ? mouseYawAdd : -mouseYawAdd));
-            }
-        } else {
-            _cumulativeMouseYaw = 0;
-        }
-        if (fabs(mouseLocationY) > MOUSE_MOVE_RADIUS) {
-            float mousePitchAdd = (fabs(mouseLocationY) - MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_PITCH_SPEED;
-            bool downPitching = (mouseLocationY > 0.f);
-            _head.setPitch(_head.getPitch() + (downPitching ? -mousePitchAdd : mousePitchAdd));
+        if (mouseLocationX > MOUSE_MOVE_RADIUS) {
+            _head.addYaw(-(mouseLocationX - MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_ROTATE_SPEED);
+        } else if (mouseLocationX < -MOUSE_MOVE_RADIUS) {
+            _head.addYaw(-(mouseLocationX + MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_ROTATE_SPEED);
         }
         
+        if (mouseLocationY > MOUSE_MOVE_RADIUS) {
+            _head.addPitch(-(mouseLocationY - MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_PITCH_SPEED);
+        } else if (mouseLocationY < -MOUSE_MOVE_RADIUS) {
+            _head.addPitch(-(mouseLocationY + MOUSE_MOVE_RADIUS) / (0.5f - MOUSE_MOVE_RADIUS) * MOUSE_PITCH_SPEED);
+        }
     }
-    
     return;
 }
 
@@ -539,19 +523,21 @@ void Avatar::simulate(float deltaTime, Transmitter* transmitter) {
         }
         
         //  Compute instantaneous acceleration
-        float acceleration = glm::distance(getVelocity(), oldVelocity) / deltaTime;
+        float forwardAcceleration = glm::length(glm::dot(getBodyFrontDirection(), getVelocity() - oldVelocity)) / deltaTime;
         const float ACCELERATION_PITCH_DECAY = 0.4f;
         const float ACCELERATION_YAW_DECAY = 0.4f;
-        
+        const float ACCELERATION_PULL_THRESHOLD = 0.2f;
         const float OCULUS_ACCELERATION_PULL_THRESHOLD = 1.0f;
         const int OCULUS_YAW_OFFSET_THRESHOLD = 10;
         
         // Decay HeadPitch as a function of acceleration, so that you look straight ahead when
         // you start moving, but don't do this with an HMD like the Oculus.
         if (!OculusManager::isConnected()) {
-            _head.setPitch(_head.getPitch() * (1.f - acceleration * ACCELERATION_PITCH_DECAY * deltaTime));
-            _head.setYaw(_head.getYaw() * (1.f - acceleration * ACCELERATION_YAW_DECAY * deltaTime));
-        } else if (fabsf(acceleration) > OCULUS_ACCELERATION_PULL_THRESHOLD
+            if (forwardAcceleration > ACCELERATION_PULL_THRESHOLD) {
+                _head.setPitch(_head.getPitch() * (1.f - forwardAcceleration * ACCELERATION_PITCH_DECAY * deltaTime));
+                _head.setYaw(_head.getYaw() * (1.f - forwardAcceleration * ACCELERATION_YAW_DECAY * deltaTime));
+            }
+        } else if (fabsf(forwardAcceleration) > OCULUS_ACCELERATION_PULL_THRESHOLD
                    && fabs(_head.getYaw()) > OCULUS_YAW_OFFSET_THRESHOLD) {
             // if we're wearing the oculus
             // and this acceleration is above the pull threshold
@@ -1304,4 +1290,4 @@ void Avatar::renderJointConnectingCone(glm::vec3 position1, glm::vec3 position2,
     }
     
     glEnd();
-}
\ No newline at end of file
+}
diff --git a/interface/src/Avatar.h b/interface/src/Avatar.h
index c1fc353a34..0fc5b31286 100644
--- a/interface/src/Avatar.h
+++ b/interface/src/Avatar.h
@@ -194,7 +194,6 @@ private:
     glm::vec3   _mouseRayOrigin;
     glm::vec3   _mouseRayDirection;
     Avatar*     _interactingOther;
-    float       _cumulativeMouseYaw;
     bool        _isMouseTurningRight;
     
     AvatarVoxelSystem _voxels;
diff --git a/interface/src/Camera.cpp b/interface/src/Camera.cpp
index 4227e623ff..9fc0033fc4 100644
--- a/interface/src/Camera.cpp
+++ b/interface/src/Camera.cpp
@@ -7,9 +7,7 @@
 #include <glm/gtx/quaternion.hpp>
 #include <SharedUtil.h>
 #include <VoxelConstants.h>
-#include <OculusManager.h>
 #include "Log.h"
-
 #include "Camera.h"
 #include "Util.h"
 
@@ -88,22 +86,19 @@ void Camera::updateFollowMode(float deltaTime) {
         t = 1.0;
     }
     
-    // update rotation (before position!)
-    if (_needsToInitialize || OculusManager::isConnected()) {
+    // Update position and rotation, setting directly if tightness is 0.0
+    
+    if (_needsToInitialize || (_tightness == 0.0f)) {
         _rotation = _targetRotation;
+        _idealPosition = _targetPosition + _rotation * glm::vec3(0.0f, _upShift, _distance);
+        _position = _idealPosition;
+        _needsToInitialize = false;
+
     } else {
         // pull rotation towards ideal
         _rotation = safeMix(_rotation, _targetRotation, t);
-    }
-            
-    _idealPosition = _targetPosition + _rotation * glm::vec3(0.0f, _upShift, _distance);
-    
-    if (_needsToInitialize) {
-        _position = _idealPosition; 
-        _needsToInitialize = false;
-    } else {
-        // force position towards ideal position
-        _position += (_idealPosition - _position) * t; 
+        _idealPosition = _targetPosition + _rotation * glm::vec3(0.0f, _upShift, _distance);
+        _position += (_idealPosition - _position) * t;
     }
 }
 
diff --git a/interface/src/SerialInterface.cpp b/interface/src/SerialInterface.cpp
index 2fa078baf4..1e472c5a11 100644
--- a/interface/src/SerialInterface.cpp
+++ b/interface/src/SerialInterface.cpp
@@ -6,6 +6,8 @@
 //
 
 #include "SerialInterface.h"
+#include <glm/gtx/vector_angle.hpp>
+#include <math.h>
 
 #ifdef __APPLE__
 #include <regex.h>
@@ -15,6 +17,7 @@
 
 const short NO_READ_MAXIMUM_MSECS = 3000;
 const int GRAVITY_SAMPLES = 60;                     //  Use the first few samples to baseline values
+const int SENSOR_FUSION_SAMPLES = 200;
 const int LONG_TERM_RATE_SAMPLES = 1000;            
 
 const bool USING_INVENSENSE_MPU9150 = 1;
@@ -227,6 +230,7 @@ void SerialInterface::readData(float deltaTime) {
 
         //  Update raw rotation estimates
         _estimatedRotation += deltaTime * (_lastRotationRates - _averageRotationRates);
+
         
         //  Update estimated position and velocity
         float const DECAY_VELOCITY = 0.95f;
@@ -235,10 +239,7 @@ void SerialInterface::readData(float deltaTime) {
         _estimatedPosition += deltaTime * _estimatedVelocity;
         _estimatedVelocity *= DECAY_VELOCITY;
         _estimatedPosition *= DECAY_POSITION;
-        
-        //glm::vec3 baseline = glm::normalize(_gravity);
-        //glm::vec3 current = glm::normalize(_lastAcceleration);
-        
+                
         //  Accumulate a set of initial baseline readings for setting gravity
         if (totalSamples == 0) {
             _averageRotationRates = _lastRotationRates;
@@ -255,8 +256,31 @@ void SerialInterface::readData(float deltaTime) {
             if (totalSamples < GRAVITY_SAMPLES) {
                 _gravity = (1.f - 1.f/(float)GRAVITY_SAMPLES) * _gravity +
                 1.f/(float)GRAVITY_SAMPLES * _lastAcceleration;
+            } else {
+                //  Use gravity reading to do sensor fusion on the pitch and roll estimation
+                float truePitchAngle = glm::angle(glm::normalize(glm::vec3(0, _gravity.y, _gravity.z)),
+                                                  glm::normalize(glm::vec3(0, _lastAcceleration.y, _lastAcceleration.z))) 
+                                       * ((_lastAcceleration.z > _gravity.z) ? -1.0 : 1.0);
+                
+                float trueRollAngle = glm::angle(glm::normalize(glm::vec3(_gravity.x, _gravity.y, 0)),
+                                                 glm::normalize(glm::vec3(_lastAcceleration.x, _lastAcceleration.y, 0))) 
+                                      * ((_lastAcceleration.x > _gravity.x) ? -1.0 : 1.0);
+                
+                //  PER:  BUG:   This is bizarre, because glm::angle() SOMETIMES returns NaN for what seem to
+                //               be perfectly valid inputs.  So I added these NaN tests,  gotta fix.  
+                if (!glm::isnan(truePitchAngle) && !glm::isnan(trueRollAngle)) {
+                    _estimatedRotation.x = (1.f - 1.f/(float)SENSOR_FUSION_SAMPLES) * _estimatedRotation.x 
+                                           + 1.f/(float)SENSOR_FUSION_SAMPLES * truePitchAngle;
+                    _estimatedRotation.z = (1.f - 1.f/(float)SENSOR_FUSION_SAMPLES) * _estimatedRotation.z 
+                                           + 1.f/(float)SENSOR_FUSION_SAMPLES * trueRollAngle;
+                    //  Without a compass heading, always decay estimated Yaw slightly
+                    const float YAW_DECAY = 0.995;
+                    _estimatedRotation.y *= YAW_DECAY;
+                }
+                
             }
         }
+         
         
         totalSamples++;
     } 
diff --git a/interface/src/Util.cpp b/interface/src/Util.cpp
index a2ea1d2916..ac401a4e8b 100644
--- a/interface/src/Util.cpp
+++ b/interface/src/Util.cpp
@@ -57,7 +57,9 @@ void eulerToOrthonormals(glm::vec3 * angles, glm::vec3 * front, glm::vec3 * righ
     front->x = frontNew.x;  front->y = frontNew.y;  front->z = frontNew.z;
 }
 
-
+void printVector(glm::vec3 vec) {
+    printf("%4.2f, %4.2f, %4.2f\n", vec.x, vec.y, vec.z);
+}
 
 //  Return the azimuth angle in degrees between two points.
 float azimuth_to(glm::vec3 head_pos, glm::vec3 source_pos) {
diff --git a/interface/src/Util.h b/interface/src/Util.h
index 0187d93da5..05e7a21525 100644
--- a/interface/src/Util.h
+++ b/interface/src/Util.h
@@ -43,6 +43,8 @@ void noiseTest(int w, int h);
 
 void drawVector(glm::vec3* vector);
 
+void printVector(glm::vec3 vec);
+
 float angleBetween(const glm::vec3& v1, const glm::vec3& v2); 
 
 glm::quat rotationBetween(const glm::vec3& v1, const glm::vec3& v2);
diff --git a/libraries/shared/src/Agent.cpp b/libraries/shared/src/Agent.cpp
index 9bddd45b84..09fe6a1459 100644
--- a/libraries/shared/src/Agent.cpp
+++ b/libraries/shared/src/Agent.cpp
@@ -119,7 +119,7 @@ void Agent::recordBytesReceived(int bytesReceived) {
 }
 
 float Agent::getAveragePacketsPerSecond() {
-    if (_bytesReceivedMovingAverage != NULL) {
+    if (_bytesReceivedMovingAverage) {
         return (1 / _bytesReceivedMovingAverage->getEventDeltaAverage());
     } else {
         return 0;
@@ -127,7 +127,7 @@ float Agent::getAveragePacketsPerSecond() {
 }
 
 float Agent::getAverageKilobitsPerSecond() {
-    if (_bytesReceivedMovingAverage != NULL) {
+    if (_bytesReceivedMovingAverage) {
         return (_bytesReceivedMovingAverage->getAverageSampleValuePerSecond() * (8.0f / 1000));
     } else {
         return 0;
diff --git a/libraries/shared/src/PacketHeaders.h b/libraries/shared/src/PacketHeaders.h
index 3e6f2ba152..f40c8abea7 100644
--- a/libraries/shared/src/PacketHeaders.h
+++ b/libraries/shared/src/PacketHeaders.h
@@ -3,7 +3,7 @@
 //  hifi
 //
 //  Created by Stephen Birarda on 4/8/13.
-//
+//  Copyright (c) 2013 HighFidelity, Inc. All rights reserved.
 //
 //  The packet headers below refer to the first byte of a received UDP packet transmitted between
 //  any two Hifi components.  For example, a packet whose first byte is 'P' is always a ping packet.
@@ -20,7 +20,8 @@ const PACKET_HEADER PACKET_HEADER_HEAD_DATA = 'H';
 const PACKET_HEADER PACKET_HEADER_Z_COMMAND = 'Z';
 const PACKET_HEADER PACKET_HEADER_INJECT_AUDIO = 'I';
 const PACKET_HEADER PACKET_HEADER_MIXED_AUDIO = 'A';
-const PACKET_HEADER PACKET_HEADER_MICROPHONE_AUDIO = 'M';
+const PACKET_HEADER PACKET_HEADER_MICROPHONE_AUDIO_NO_ECHO = 'M';
+const PACKET_HEADER PACKET_HEADER_MICROPHONE_AUDIO_WITH_ECHO = 'm';
 const PACKET_HEADER PACKET_HEADER_SET_VOXEL = 'S';
 const PACKET_HEADER PACKET_HEADER_SET_VOXEL_DESTRUCTIVE = 'O';
 const PACKET_HEADER PACKET_HEADER_ERASE_VOXEL = 'E';