diff --git a/sdrbase/audio/audioopus.cpp b/sdrbase/audio/audioopus.cpp
index 4f9eaa082..332809b33 100644
--- a/sdrbase/audio/audioopus.cpp
+++ b/sdrbase/audio/audioopus.cpp
@@ -86,6 +86,12 @@ int AudioOpus::encode(int frameSize, int16_t *in, uint8_t *out)
 {
     QMutexLocker mutexLocker(&m_mutex);
 
+    if (!m_encoderOK)
+    {
+        qWarning("AudioOpus::encode: encoder not initialized");
+        return 0;
+    }
+
     int nbBytes = opus_encode(m_encoderState, in, frameSize, out, m_maxPacketSize);
 
     if (nbBytes < 0)
diff --git a/sdrbase/sdrbase.pro b/sdrbase/sdrbase.pro
index 0a295936d..7d49d1af2 100644
--- a/sdrbase/sdrbase.pro
+++ b/sdrbase/sdrbase.pro
@@ -139,7 +139,7 @@ HEADERS  += audio/audiodevicemanager.h\
         audio/audiocompressor.h\
         audio/audiofifo.h\
         audio/audiofilter.h\
-        audio/audiog722.h\        
+        audio/audiog722.h\
         audio/audioopus.h\
         audio/audiooutput.h\
         audio/audioinput.h\
@@ -235,7 +235,7 @@ HEADERS  += audio/audiodevicemanager.h\
         mainparser.h
 
 MSVC {
-    LIBS += -LC:\softs\libopus_v1.3_msvc15\lib\x64 -lopus
+    LIBS += -LC:\softs\libopus_v1.3_msvc15\bin\x64 -LC:\softs\libopus_v1.3_msvc15\lib\x64 -lopus
 }
 MINGW32 || MINGW64 || MSVC {
     LIBS += -L../serialdv/$${build_subdir} -lserialdv
diff --git a/sdrgui/audio.md b/sdrgui/audio.md
index 3c158acde..c8eee3e7e 100644
--- a/sdrgui/audio.md
+++ b/sdrgui/audio.md
@@ -67,7 +67,7 @@ This is the codec applied before sending the stream via UDP. The following are a
   - `PCMA`: A-law 8 bit PCM (requires 8000 Hz sample rate mono)
   - `PCMU`: Mu-law 8 bit PCM (requires 8000 Hz sample rate mono)
   - `G722`: G722 64 kbit/s (requires 16000 Hz sample rate mono)
-  - `OPUS` : Opus constant 64 kbit/s (requires 48, 24, 16 or 12 kHz sample rates)
+  - `opus` : Opus constant 64 kbit/s (requires 48, 24, 16 or 12 kHz sample rates. 48 kHz makes more sense when using Opus)
 
 <h3>1.10 SDP string</h3>
 
@@ -90,18 +90,18 @@ Use this button to activate or de-activate the copy of the audio stream to UDP s
 Check this box to activate the RTP protocol over UDP. RTP parameters are as follows:
 
   - Payload type:
-    - codec `L16`, `L8`: 96
-    - codec `OPUS`: 101
+    - codec `L16`, `L8`, `opus`: 96
     - codec `PCMA`: 8
     - codec `PCMU`: 0
     - codec `G722`: 9
   - Sample rate: the resulting stream sample rate after decimation and possible compression:
     - codec `PCMA`, `PCMU`: must be 8000 S/s
     - codec `G722`: must be 8000 S/s (16000 S/s input before compression)
+    - codec `opus`: timestamp increment is that of 20ms @ 48kHz i.e. 960 but actual payload and sample rate is 160 bytes at 8 kHz
   - Sample format:
     - codec `L16`: 16 bit integer signed (S16LE)
     - codec `L8`, `PCMA`, `PCMU`: 8 bit integer signed (S8)
-    - codec `G722`, `OPUS`: 8 bit unsigned integer. Note that this is the stream compressed to 64 kbits/s.
+    - codec `G722`, `opus`: 8 bit unsigned integer. Note that this is the stream compressed to 64 kbits/s.
   - Channels: 1 for mono (Left, Right and Mixed copy channels mode); 2 for stereo (Stereo copy channels mode)
   - Address and port: destination address and port (local on the client machine)
 
diff --git a/windowsms.install.bat b/windowsms.install.bat
index 7ab7407a5..5a253e301 100644
--- a/windowsms.install.bat
+++ b/windowsms.install.bat
@@ -7,6 +7,7 @@ SET pothosdir="C:\Program Files\PothosSDR"
 SET pthreadsdir="C:\softs\pthreads-w32"
 SET ffmpegdir="C:\softs\ffmpeg-20181127-1035206-win64-shared\bin"
 SET qt5dir="C:\Qt\5.11.1\msvc2017_64\bin"
+SET libopusdir="C:\softs\libopus_v1.3_msvc15\bin\x64"
 
 copy app\%1\sdrangel.exe %2
 copy sdrbase\%1\sdrbase.dll %2
@@ -43,6 +44,7 @@ REM copy %opencvdir%\libopencv_highgui2413.dll %2
 REM copy %opencvdir%\libopencv_core2413.dll %2
 copy %ffmpegdir%\*.dll %2
 copy %qt5dir%\Qt5Qml.dll %2
+copy %libopusdir%\opus.dll %2
 
 mkdir %2\plugins
 mkdir %2\plugins\channelrx