diff --git a/sdrbase/dsp/dvserialengine.cpp b/sdrbase/dsp/dvserialengine.cpp
index 624ebf298..48a6ce30e 100644
--- a/sdrbase/dsp/dvserialengine.cpp
+++ b/sdrbase/dsp/dvserialengine.cpp
@@ -250,17 +250,18 @@ void DVSerialEngine::pushMbeFrame(const unsigned char *mbeFrame, int mbeRateInde
     std::vector<DVSerialController>::iterator it = m_controllers.begin();
     std::vector<DVSerialController>::iterator itAvail = m_controllers.end();
     bool done = false;
+    unsigned int fifoSlot;
     QMutexLocker locker(&m_mutex);
 
     while (it != m_controllers.end())
     {
-        if (it->worker->hasFifo(audioFifo))
+        if (it->worker->hasFifo(audioFifo, fifoSlot))
         {
-            it->worker->pushMbeFrame(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo);
+            it->worker->pushMbeFrame(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo, fifoSlot);
             done = true;
             break;
         }
-        else if (it->worker->isAvailable())
+        else if (it->worker->isAvailable(fifoSlot))
         {
             itAvail = it;
             break;
@@ -276,7 +277,7 @@ void DVSerialEngine::pushMbeFrame(const unsigned char *mbeFrame, int mbeRateInde
             int wNum = itAvail - m_controllers.begin();
 
             qDebug("DVSerialEngine::pushMbeFrame: push %p on empty queue %d", audioFifo, wNum);
-            itAvail->worker->pushMbeFrame(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo);
+            itAvail->worker->pushMbeFrame(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo, fifoSlot);
         }
         else
         {
diff --git a/sdrbase/dsp/dvserialworker.cpp b/sdrbase/dsp/dvserialworker.cpp
index a15008ff1..610efe547 100644
--- a/sdrbase/dsp/dvserialworker.cpp
+++ b/sdrbase/dsp/dvserialworker.cpp
@@ -72,7 +72,12 @@ void DVSerialWorker::handleInputMessages()
 {
     Message* message;
     m_audioBufferFill = 0;
-    AudioFifo *audioFifo = 0;
+    AudioFifo *audioFifo[m_nbFifoSlots];
+
+    for (int i = 0; i < m_nbFifoSlots; i++)
+    {
+        audioFifo[i] = 0;
+    }
 
     while ((message = m_inputMessageQueue.pop()) != 0)
     {
@@ -84,7 +89,7 @@ void DVSerialWorker::handleInputMessages()
             if (m_dvController.decode(m_dvAudioSamples, decodeMsg->getMbeFrame(), decodeMsg->getMbeRate(), dBVolume))
             {
                 upsample6(m_dvAudioSamples, SerialDV::MBE_AUDIO_BLOCK_SIZE, decodeMsg->getChannels(), decodeMsg->getAudioFifo());
-                audioFifo = decodeMsg->getAudioFifo();
+                audioFifo[decodeMsg->getFifoSlot()] = decodeMsg->getAudioFifo();
             }
             else
             {
@@ -95,40 +100,60 @@ void DVSerialWorker::handleInputMessages()
         delete message;
     }
 
-    if (audioFifo)
+    for (int i = 0; i < m_nbFifoSlots; i++)
     {
-        uint res = audioFifo->write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 10);
-
-        if (res != m_audioBufferFill)
+        if (audioFifo[i])
         {
-            qDebug("DVSerialWorker::handleInputMessages: %u/%u audio samples written", res, m_audioBufferFill);
+            uint res = audioFifo[i]->write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 10);
+
+            if (res != m_audioBufferFill)
+            {
+                qDebug("DVSerialWorker::handleInputMessages: %u/%u audio samples written", res, m_audioBufferFill);
+            }
+
+            m_fifoSlots[i].m_timestamp = QDateTime::currentDateTime();
         }
     }
-
-    m_fifoSlots[0].m_timestamp = QDateTime::currentDateTime();
 }
 
 void DVSerialWorker::pushMbeFrame(const unsigned char *mbeFrame,
         int mbeRateIndex,
         int mbeVolumeIndex,
-        unsigned char channels, AudioFifo *audioFifo)
+        unsigned char channels, AudioFifo *audioFifo,
+        unsigned int fifoSlot)
 {
     m_fifoSlots[0].m_audioFifo = audioFifo;
-    m_inputMessageQueue.push(MsgMbeDecode::create(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo));
+    m_inputMessageQueue.push(MsgMbeDecode::create(mbeFrame, mbeRateIndex, mbeVolumeIndex, channels, audioFifo, fifoSlot));
 }
 
-bool DVSerialWorker::isAvailable()
+bool DVSerialWorker::isAvailable(unsigned int& fifoSlot)
 {
-	if (m_fifoSlots[0].m_audioFifo == 0) {
-		return true;
-	}
+    for (fifoSlot = 0; fifoSlot < m_nbFifoSlots; fifoSlot++)
+    {
+        if (m_fifoSlots[fifoSlot].m_audioFifo == 0)
+        {
+            return true;
+        }
+        else if (m_fifoSlots[fifoSlot].m_timestamp.time().msecsTo(QDateTime::currentDateTime().time()) > 1000)
+        {
+            return true;
+        }
+    }
 
-	return m_fifoSlots[0].m_timestamp.time().msecsTo(QDateTime::currentDateTime().time()) > 1000; // 1 second inactivity timeout
+	return false;
 }
 
-bool DVSerialWorker::hasFifo(AudioFifo *audioFifo)
+bool DVSerialWorker::hasFifo(AudioFifo *audioFifo, unsigned int& fifoSlot)
 {
-    return m_fifoSlots[0].m_audioFifo == audioFifo;
+    for (fifoSlot = 0; fifoSlot < m_nbFifoSlots; fifoSlot++)
+    {
+        if (m_fifoSlots[fifoSlot].m_audioFifo == audioFifo)
+        {
+            return true;
+        }
+    }
+
+    return false;
 }
 
 void DVSerialWorker::upsample6(short *in, int nbSamplesIn, unsigned char channels, AudioFifo *audioFifo)
diff --git a/sdrbase/dsp/dvserialworker.h b/sdrbase/dsp/dvserialworker.h
index 9192b8b7c..ec74d1583 100644
--- a/sdrbase/dsp/dvserialworker.h
+++ b/sdrbase/dsp/dvserialworker.h
@@ -54,10 +54,17 @@ public:
         int getVolumeIndex() const { return m_volumeIndex; }
         unsigned char getChannels() const { return m_channels % 4; }
         AudioFifo *getAudioFifo() { return m_audioFifo; }
+        unsigned int getFifoSlot() const { return m_fifoSlot; }
 
-        static MsgMbeDecode* create(const unsigned char *mbeFrame, int mbeRateIndex, int volumeIndex, unsigned char channels, AudioFifo *audioFifo)
+        static MsgMbeDecode* create(
+                const unsigned char *mbeFrame,
+                int mbeRateIndex,
+                int volumeIndex,
+                unsigned char channels,
+                AudioFifo *audioFifo,
+                unsigned int fifoSlot)
         {
-            return new MsgMbeDecode(mbeFrame, (SerialDV::DVRate) mbeRateIndex, volumeIndex, channels, audioFifo);
+            return new MsgMbeDecode(mbeFrame, (SerialDV::DVRate) mbeRateIndex, volumeIndex, channels, audioFifo, fifoSlot);
         }
 
     private:
@@ -66,17 +73,20 @@ public:
         int m_volumeIndex;
         unsigned char m_channels;
         AudioFifo *m_audioFifo;
+        unsigned int m_fifoSlot;
 
         MsgMbeDecode(const unsigned char *mbeFrame,
                 SerialDV::DVRate mbeRate,
                 int volumeIndex,
                 unsigned char channels,
-                AudioFifo *audioFifo) :
+                AudioFifo *audioFifo,
+                unsigned int fifoSlot) :
             Message(),
             m_mbeRate(mbeRate),
             m_volumeIndex(volumeIndex),
             m_channels(channels),
-            m_audioFifo(audioFifo)
+            m_audioFifo(audioFifo),
+            m_fifoSlot(fifoSlot)
         {
             memcpy((void *) m_mbeFrame, (const void *) mbeFrame, SerialDV::DVController::getNbMbeBytes(m_mbeRate));
         }
@@ -89,14 +99,15 @@ public:
             int mbeRateIndex,
             int mbeVolumeIndex,
             unsigned char channels,
-            AudioFifo *audioFifo);
+            AudioFifo *audioFifo,
+            unsigned int fifoSlot);
 
     bool open(const std::string& serialDevice);
     void close();
     void process();
     void stop();
-    bool isAvailable();
-    bool hasFifo(AudioFifo *audioFifo);
+    bool isAvailable(unsigned int& fifoSlot);
+    bool hasFifo(AudioFifo *audioFifo, unsigned int& fifoSlot);
 
     void postTest()
     {
@@ -138,7 +149,8 @@ private:
     //short m_audioSamples[SerialDV::MBE_AUDIO_BLOCK_SIZE * 6 * 2]; // upsample to 48k and duplicate channel
     AudioVector m_audioBuffer;
     uint m_audioBufferFill;
-    FifoSlot m_fifoSlots[2];
+    static const unsigned int m_nbFifoSlots = 1;
+    FifoSlot m_fifoSlots[m_nbFifoSlots];
     short m_upsamplerLastValue;
     float m_phase;
     MBEAudioInterpolatorFilter m_upsampleFilter;