diff --git a/autobuild.xml b/autobuild.xml
index c2d063763d..37a04862da 100644
--- a/autobuild.xml
+++ b/autobuild.xml
@@ -745,18 +745,6 @@
       </map>
       <key>glm</key>
       <map>
-        <key>canonical_repo</key>
-        <string>https://github.com/secondlife/3p-glm</string>
-        <key>copyright</key>
-        <string>Copyright (c) 2005 - G-Truc Creation</string>
-        <key>description</key>
-        <string>OpenGL Mathematics</string>
-        <key>license</key>
-        <string>MIT</string>
-        <key>license_file</key>
-        <string>LICENSES/glm_license.txt</string>
-        <key>name</key>
-        <string>glm</string>
         <key>platforms</key>
         <map>
           <key>common</key>
@@ -774,16 +762,28 @@
             <string>common</string>
           </map>
         </map>
-        <key>source_type</key>
-        <string>git</string>
+        <key>license</key>
+        <string>MIT</string>
+        <key>license_file</key>
+        <string>LICENSES/glm_license.txt</string>
+        <key>copyright</key>
+        <string>Copyright (c) 2005 - G-Truc Creation</string>
+        <key>version</key>
+        <string>v1.0.1</string>
+        <key>name</key>
+        <string>glm</string>
         <key>vcs_branch</key>
         <string>refs/tags/v1.0.1-r1</string>
         <key>vcs_revision</key>
         <string>399cd5ba57a9267a560ce07e50a0f8c5fe3dc66f</string>
         <key>vcs_url</key>
         <string>git://github.com/secondlife/3p-glm.git</string>
-        <key>version</key>
-        <string>v1.0.1</string>
+        <key>canonical_repo</key>
+        <string>https://github.com/secondlife/3p-glm</string>
+        <key>description</key>
+        <string>OpenGL Mathematics</string>
+        <key>source_type</key>
+        <string>git</string>
       </map>
       <key>gstreamer</key>
       <map>
@@ -1418,14 +1418,6 @@
       </map>
       <key>llphysicsextensions_source</key>
       <map>
-        <key>copyright</key>
-        <string>Copyright (c) 2010, Linden Research, Inc.</string>
-        <key>license</key>
-        <string>internal</string>
-        <key>license_file</key>
-        <string>LICENSES/llphysicsextensions.txt</string>
-        <key>name</key>
-        <string>llphysicsextensions_source</string>
         <key>platforms</key>
         <map>
           <key>darwin64</key>
@@ -1477,8 +1469,16 @@
             <string>windows64</string>
           </map>
         </map>
+        <key>license</key>
+        <string>internal</string>
+        <key>license_file</key>
+        <string>LICENSES/llphysicsextensions.txt</string>
+        <key>copyright</key>
+        <string>Copyright (c) 2010, Linden Research, Inc.</string>
         <key>version</key>
         <string>1.0.b8b1f73</string>
+        <key>name</key>
+        <string>llphysicsextensions_source</string>
       </map>
       <key>llphysicsextensions_stub</key>
       <map>
@@ -2008,16 +2008,6 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
       </map>
       <key>openal</key>
       <map>
-        <key>copyright</key>
-        <string>Copyright (C) 1999-2007 by authors.</string>
-        <key>description</key>
-        <string>OpenAL Soft is a software implementation of the OpenAL 3D audio API.</string>
-        <key>license</key>
-        <string>LGPL2</string>
-        <key>license_file</key>
-        <string>LICENSES/openal-soft.txt</string>
-        <key>name</key>
-        <string>openal</string>
         <key>platforms</key>
         <map>
           <key>darwin64</key>
@@ -2063,8 +2053,18 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
             <string>windows64</string>
           </map>
         </map>
+        <key>license</key>
+        <string>LGPL2</string>
+        <key>license_file</key>
+        <string>LICENSES/openal-soft.txt</string>
+        <key>copyright</key>
+        <string>Copyright (C) 1999-2007 by authors.</string>
         <key>version</key>
         <string>1.23.1</string>
+        <key>name</key>
+        <string>openal</string>
+        <key>description</key>
+        <string>OpenAL Soft is a software implementation of the OpenAL 3D audio API.</string>
       </map>
       <key>openjpeg</key>
       <map>
@@ -2793,11 +2793,11 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>194b4f5957c9f003c46e61a434e23a7c3d1180d6</string>
+              <string>3570b6442d472cd97bad8622c2ec2571d72218a0</string>
               <key>hash_algorithm</key>
               <string>sha1</string>
               <key>url</key>
-              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.70-debug/webrtc-m114.5735.08.70-debug.10377605436-darwin64-10377605436.tar.zst</string>
+              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.72-test/webrtc-m114.5735.08.72-test.10444682919-darwin64-10444682919.tar.zst</string>
             </map>
             <key>name</key>
             <string>darwin64</string>
@@ -2807,11 +2807,11 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>38e0c7d30b4c40eb04e60ab199440b847cc7c6cf</string>
+              <string>eadf6aa99313940ded11801d42c11375669f1628</string>
               <key>hash_algorithm</key>
               <string>sha1</string>
               <key>url</key>
-              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.70-debug/webrtc-m114.5735.08.70-debug.10377605436-linux64-10377605436.tar.zst</string>
+              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.72-test/webrtc-m114.5735.08.72-test.10444682919-linux64-10444682919.tar.zst</string>
             </map>
             <key>name</key>
             <string>linux64</string>
@@ -2821,11 +2821,11 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
             <key>archive</key>
             <map>
               <key>hash</key>
-              <string>053fb5c873df9192e34cddcf2db1c5fdcff76ba1</string>
+              <string>0081fd35290adbc8e66dd366535fb6cd8a966f1e</string>
               <key>hash_algorithm</key>
               <string>sha1</string>
               <key>url</key>
-              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.70-debug/webrtc-m114.5735.08.70-debug.10377605436-windows64-10377605436.tar.zst</string>
+              <string>https://github.com/secondlife/3p-webrtc-build/releases/download/m114.5735.08.72-test/webrtc-m114.5735.08.72-test.10444682919-windows64-10444682919.tar.zst</string>
             </map>
             <key>name</key>
             <string>windows64</string>
@@ -2838,7 +2838,7 @@ Copyright (c) 2012, 2014, 2015, 2016 nghttp2 contributors</string>
         <key>copyright</key>
         <string>Copyright (c) 2011, The WebRTC project authors. All rights reserved.</string>
         <key>version</key>
-        <string>m114.5735.08.70-debug.10377605436</string>
+        <string>m114.5735.08.72-test.10444682919</string>
         <key>name</key>
         <string>webrtc</string>
         <key>vcs_branch</key>
diff --git a/indra/llwebrtc/CMakeLists.txt b/indra/llwebrtc/CMakeLists.txt
index 30aaec1265..a18b716003 100644
--- a/indra/llwebrtc/CMakeLists.txt
+++ b/indra/llwebrtc/CMakeLists.txt
@@ -31,6 +31,7 @@ add_library (llwebrtc SHARED ${llwebrtc_SOURCE_FILES})
 set_target_properties(llwebrtc PROPERTIES PUBLIC_HEADER llwebrtc.h)
 
 if (WINDOWS)
+    cmake_policy(SET CMP0091 NEW)
     set_target_properties(llwebrtc
         PROPERTIES
         LINK_FLAGS "/debug /LARGEADDRESSAWARE"
@@ -42,7 +43,10 @@ if (WINDOWS)
                                        wmcodecdspuuid
                                        msdmo
                                        strmiids
-                                       iphlpapi)
+                                       iphlpapi
+                                       libcmt)
+    # as the webrtc libraries are release, build this binary as release as well.
+    target_compile_options(llwebrtc PRIVATE "/MT")
     if (USE_BUGSPLAT)
         set_target_properties(llwebrtc PROPERTIES PDB_OUTPUT_DIRECTORY "${SYMBOLS_STAGING_DIR}")
     endif (USE_BUGSPLAT)
diff --git a/indra/llwebrtc/llwebrtc.cpp b/indra/llwebrtc/llwebrtc.cpp
index 2c890acbdb..0daa767766 100644
--- a/indra/llwebrtc/llwebrtc.cpp
+++ b/indra/llwebrtc/llwebrtc.cpp
@@ -206,10 +206,10 @@ void LLWebRTCImpl::init()
             mTuningDeviceModule->SetAudioDeviceSink(this);
             mTuningDeviceModule->InitMicrophone();
             mTuningDeviceModule->InitSpeaker();
+            mTuningDeviceModule->SetStereoRecording(false);
+            mTuningDeviceModule->SetStereoPlayout(true);
             mTuningDeviceModule->InitRecording();
             mTuningDeviceModule->InitPlayout();
-            mTuningDeviceModule->SetStereoRecording(true);
-            mTuningDeviceModule->SetStereoPlayout(true);
             updateDevices();
         });
 
@@ -227,10 +227,6 @@ void LLWebRTCImpl::init()
             mPeerDeviceModule->EnableBuiltInAEC(false);
             mPeerDeviceModule->InitMicrophone();
             mPeerDeviceModule->InitSpeaker();
-            mPeerDeviceModule->InitRecording();
-            mPeerDeviceModule->InitPlayout();
-            mPeerDeviceModule->SetStereoRecording(true);
-            mPeerDeviceModule->SetStereoPlayout(true);
         });
 
     // The custom processor allows us to retrieve audio data (and levels)
@@ -251,8 +247,9 @@ void LLWebRTCImpl::init()
     apm_config.noise_suppression.level        = webrtc::AudioProcessing::Config::NoiseSuppression::kVeryHigh;
     apm_config.transient_suppression.enabled  = true;
     apm_config.pipeline.multi_channel_render  = true;
-    apm_config.pipeline.multi_channel_capture = true;
-    apm_config.pipeline.multi_channel_capture = true;
+    apm_config.pipeline.multi_channel_capture = false;
+
+    mAudioProcessingModule->ApplyConfig(apm_config);
 
     webrtc::ProcessingConfig processing_config;
     processing_config.input_stream().set_num_channels(2);
@@ -264,10 +261,8 @@ void LLWebRTCImpl::init()
     processing_config.reverse_output_stream().set_num_channels(2);
     processing_config.reverse_output_stream().set_sample_rate_hz(48000);
 
-    mAudioProcessingModule->ApplyConfig(apm_config);
     mAudioProcessingModule->Initialize(processing_config);
 
-
     mPeerConnectionFactory = webrtc::CreatePeerConnectionFactory(mNetworkThread.get(),
                                                                  mWorkerThread.get(),
                                                                  mSignalingThread.get(),
@@ -279,7 +274,6 @@ void LLWebRTCImpl::init()
                                                                  nullptr /* audio_mixer */,
                                                                  mAudioProcessingModule);
 
-    mWorkerThread->BlockingCall([this]() { mPeerDeviceModule->StartPlayout(); });
 }
 
 void LLWebRTCImpl::terminate()
@@ -331,6 +325,8 @@ void LLWebRTCImpl::setRecording(bool recording)
         {
             if (recording)
             {
+                mPeerDeviceModule->SetStereoRecording(false);
+                mPeerDeviceModule->InitRecording();
                 mPeerDeviceModule->StartRecording();
             }
             else
@@ -340,6 +336,24 @@ void LLWebRTCImpl::setRecording(bool recording)
         });
 }
 
+void LLWebRTCImpl::setPlayout(bool playing)
+{
+    mWorkerThread->PostTask(
+        [this, playing]()
+        {
+            if (playing)
+            {
+                mPeerDeviceModule->SetStereoPlayout(true);
+                mPeerDeviceModule->InitPlayout();
+                mPeerDeviceModule->StartPlayout();
+            }
+            else
+            {
+                mPeerDeviceModule->StopPlayout();
+            }
+        });
+}
+
 void LLWebRTCImpl::setAudioConfig(LLWebRTCDeviceInterface::AudioConfig config)
 {
     webrtc::AudioProcessing::Config apm_config;
@@ -402,7 +416,6 @@ void LLWebRTCImpl::unsetDevicesObserver(LLWebRTCDevicesObserver *observer)
 
 void ll_set_device_module_capture_device(rtc::scoped_refptr<webrtc::AudioDeviceModule> device_module, int16_t device)
 {
-    device_module->StopRecording();
 #if WEBRTC_WIN
     if (device < 0)
     {
@@ -417,10 +430,9 @@ void ll_set_device_module_capture_device(rtc::scoped_refptr<webrtc::AudioDeviceM
     // has it at 0
     device_module->SetRecordingDevice(device + 1);
 #endif
+    device_module->SetStereoRecording(false);
     device_module->InitMicrophone();
     device_module->InitRecording();
-    device_module->SetStereoRecording(false);
-    device_module->StartRecording();
 }
 
 void LLWebRTCImpl::setCaptureDevice(const std::string &id)
@@ -444,18 +456,32 @@ void LLWebRTCImpl::setCaptureDevice(const std::string &id)
     mRecordingDevice = recordingDevice;
     if (mTuningMode)
     {
-        mWorkerThread->PostTask([this, recordingDevice]() { ll_set_device_module_capture_device(mTuningDeviceModule, recordingDevice); });
+        mWorkerThread->PostTask([this, recordingDevice]()
+            {
+                ll_set_device_module_capture_device(mTuningDeviceModule, recordingDevice);
+            });
     }
     else
     {
-        mWorkerThread->PostTask([this, recordingDevice]() { ll_set_device_module_capture_device(mPeerDeviceModule, recordingDevice); });
+        mWorkerThread->PostTask([this, recordingDevice]()
+            {
+                bool recording = mPeerDeviceModule->Recording();
+                if (recording)
+                {
+                    mPeerDeviceModule->StopRecording();
+                }
+                ll_set_device_module_capture_device(mPeerDeviceModule, recordingDevice);
+                if (recording)
+                {
+                    mPeerDeviceModule->StartRecording();
+                }
+            });
     }
 }
 
 
 void ll_set_device_module_render_device(rtc::scoped_refptr<webrtc::AudioDeviceModule> device_module, int16_t device)
 {
-    device_module->StopPlayout();
 #if WEBRTC_WIN
     if (device < 0)
     {
@@ -468,9 +494,9 @@ void ll_set_device_module_render_device(rtc::scoped_refptr<webrtc::AudioDeviceMo
 #else
     device_module->SetPlayoutDevice(device + 1);
 #endif
+    device_module->SetStereoPlayout(true);
     device_module->InitSpeaker();
     device_module->InitPlayout();
-    device_module->SetStereoPlayout(true);
 }
 
 void LLWebRTCImpl::setRenderDevice(const std::string &id)
@@ -506,8 +532,16 @@ void LLWebRTCImpl::setRenderDevice(const std::string &id)
         mWorkerThread->PostTask(
             [this, playoutDevice]()
             {
+                bool playing = mPeerDeviceModule->Playing();
+                if (playing)
+                {
+                    mPeerDeviceModule->StopPlayout();
+                }
                 ll_set_device_module_render_device(mPeerDeviceModule, playoutDevice);
-                mPeerDeviceModule->StartPlayout();
+                if (playing)
+                {
+                    mPeerDeviceModule->StartPlayout();
+                }
             });
     }
 }
@@ -592,6 +626,8 @@ void LLWebRTCImpl::setTuningMode(bool enable)
                 //mTuningDeviceModule->StopPlayout();
                 ll_set_device_module_render_device(mPeerDeviceModule, mPlayoutDevice);
                 ll_set_device_module_capture_device(mPeerDeviceModule, mRecordingDevice);
+                mPeerDeviceModule->SetStereoPlayout(true);
+                mPeerDeviceModule->SetStereoRecording(false);
                 mPeerDeviceModule->InitPlayout();
                 mPeerDeviceModule->InitRecording();
                 mPeerDeviceModule->StartPlayout();
@@ -635,6 +671,11 @@ LLWebRTCPeerConnectionInterface *LLWebRTCImpl::newPeerConnection()
 
     mPeerConnections.emplace_back(peerConnection);
     peerConnection->enableSenderTracks(!mMute);
+    if (mPeerConnections.empty())
+    {
+        setRecording(true);
+        setPlayout(true);
+    }
     return peerConnection.get();
 }
 
@@ -649,6 +690,7 @@ void LLWebRTCImpl::freePeerConnection(LLWebRTCPeerConnectionInterface* peer_conn
     if (mPeerConnections.empty())
     {
         setRecording(false);
+        setPlayout(false);
     }
 }
 
@@ -662,7 +704,7 @@ void LLWebRTCImpl::freePeerConnection(LLWebRTCPeerConnectionInterface* peer_conn
 LLWebRTCPeerConnectionImpl::LLWebRTCPeerConnectionImpl() :
     mWebRTCImpl(nullptr),
     mPeerConnection(nullptr),
-    mMute(false),
+    mMute(true),
     mAnswerReceived(false)
 {
 }
@@ -684,8 +726,8 @@ void LLWebRTCPeerConnectionImpl::init(LLWebRTCImpl * webrtc_impl)
 }
 void LLWebRTCPeerConnectionImpl::terminate()
 {
-    mWebRTCImpl->PostSignalingTask(
-        [=]()
+    mWebRTCImpl->SignalingBlockingCall(
+        [this]()
         {
             if (mPeerConnection)
             {
diff --git a/indra/llwebrtc/llwebrtc_impl.h b/indra/llwebrtc/llwebrtc_impl.h
index c5b32123eb..f8a7873af8 100644
--- a/indra/llwebrtc/llwebrtc_impl.h
+++ b/indra/llwebrtc/llwebrtc_impl.h
@@ -278,6 +278,8 @@ class LLWebRTCImpl : public LLWebRTCDeviceInterface, public webrtc::AudioDeviceS
     // enables/disables capture via the capture device
     void setRecording(bool recording);
 
+    void setPlayout(bool playing);
+
   protected:
     LLWebRTCLogSink*                                           mLogSink;