diff --git a/plugins/feature/afc/afc.cpp b/plugins/feature/afc/afc.cpp
index 9ae3f10f9..48f2ecdd0 100644
--- a/plugins/feature/afc/afc.cpp
+++ b/plugins/feature/afc/afc.cpp
@@ -47,7 +47,8 @@ AFC::AFC(WebAPIAdapterInterface *webAPIAdapterInterface) :
     Feature(m_featureIdURI, webAPIAdapterInterface),
     m_trackerDeviceSet(nullptr),
     m_trackedDeviceSet(nullptr),
-    m_trackerIndexInDeviceSet(-1)
+    m_trackerIndexInDeviceSet(-1),
+    m_trackerChannelAPI(nullptr)
 {
     setObjectName(m_featureId);
     m_worker = new AFCWorker(webAPIAdapterInterface);
@@ -62,7 +63,7 @@ AFC::~AFC()
     }
 
     delete m_worker;
-    removeTrackerFeatureReferences();
+    removeTrackerFeatureReference();
     removeTrackedFeatureReferences();
 }
 
@@ -141,6 +142,11 @@ bool AFC::handleMessage(const Message& cmd)
     }
     else if (MsgDevicesApply::match(cmd))
     {
+        removeTrackerFeatureReference();
+        trackerDeviceChange(m_settings.m_trackerDeviceSetIndex);
+        removeTrackedFeatureReferences();
+        trackedDeviceChange(m_settings.m_trackedDeviceSetIndex);
+
         if (m_worker->isRunning())
         {
             AFCWorker::MsgDevicesApply *msg = AFCWorker::MsgDevicesApply::create();
@@ -221,11 +227,13 @@ void AFC::applySettings(const AFCSettings& settings, bool force)
 
     if ((m_settings.m_trackerDeviceSetIndex != settings.m_trackerDeviceSetIndex) || force)
     {
+        removeTrackerFeatureReference();
         trackerDeviceChange(settings.m_trackerDeviceSetIndex);
     }
 
     if ((m_settings.m_trackedDeviceSetIndex != settings.m_trackedDeviceSetIndex) || force)
     {
+        removeTrackedFeatureReferences();
         trackedDeviceChange(settings.m_trackedDeviceSetIndex);
     }
 
@@ -524,6 +532,7 @@ void AFC::trackerDeviceChange(int deviceIndex)
         if (channel->getURI() == "sdrangel.channel.freqtracker")
         {
             channel->addFeatureSettingsFeedback(this);
+            m_trackerChannelAPI = channel;
             break;
         }
     }
@@ -546,41 +555,26 @@ void AFC::trackedDeviceChange(int deviceIndex)
     }
 }
 
-void AFC::removeTrackerFeatureReferences()
+void AFC::removeTrackerFeatureReference()
 {
-    MainCore *mainCore = MainCore::instance();
-    m_trackerIndexInDeviceSet = -1;
-
-    if ((m_settings.m_trackerDeviceSetIndex >= 0) && (m_settings.m_trackerDeviceSetIndex < mainCore->getDeviceSets().size()))
+    if (m_trackerChannelAPI)
     {
-        DeviceSet *trackerDeviceSet = mainCore->getDeviceSets()[m_settings.m_trackerDeviceSetIndex];
-
-        if (trackerDeviceSet == m_trackerDeviceSet)
-        {
-            for (int i = 0; i < m_trackerDeviceSet->getNumberOfChannels(); i++)
-            {
-                ChannelAPI *channel = m_trackerDeviceSet->getChannelAt(i);
-                channel->removeFeatureSettingsFeedback(this);
-            }
+        if (MainCore::instance()->existsChannel(m_trackerChannelAPI)) {
+            m_trackerChannelAPI->removeFeatureSettingsFeedback(this);
         }
     }
 }
 
 void AFC::removeTrackedFeatureReferences()
 {
-    MainCore *mainCore = MainCore::instance();
-
-    if ((m_settings.m_trackedDeviceSetIndex >= 0) && (m_settings.m_trackedDeviceSetIndex < mainCore->getDeviceSets().size()))
+    for (QList<ChannelAPI*>::iterator it = m_trackedChannelAPIs.begin(); it != m_trackedChannelAPIs.end(); ++it)
     {
-        DeviceSet *trackerDeviceSet = mainCore->getDeviceSets()[m_settings.m_trackedDeviceSetIndex];
+        ChannelAPI *channel = *it;
 
-        if (trackerDeviceSet == m_trackedDeviceSet)
-        {
-            for (int i = 0; i < m_trackedDeviceSet->getNumberOfChannels(); i++)
-            {
-                ChannelAPI *channel = m_trackedDeviceSet->getChannelAt(i);
-                channel->removeFeatureSettingsFeedback(this);
-            }
+        if (MainCore::instance()->existsChannel(channel)) {
+            channel->removeFeatureSettingsFeedback(this);
         }
     }
+
+    m_trackedChannelAPIs.clear();
 }
diff --git a/plugins/feature/afc/afc.h b/plugins/feature/afc/afc.h
index 6d169bbd1..a735f42db 100644
--- a/plugins/feature/afc/afc.h
+++ b/plugins/feature/afc/afc.h
@@ -161,6 +161,8 @@ private:
     DeviceSet *m_trackerDeviceSet;
     DeviceSet *m_trackedDeviceSet;
     int m_trackerIndexInDeviceSet;
+    ChannelAPI *m_trackerChannelAPI;
+    QList<ChannelAPI*> m_trackedChannelAPIs;
 
     QNetworkAccessManager *m_networkManager;
     QNetworkRequest m_networkRequest;
@@ -172,7 +174,7 @@ private:
     void webapiReverseSendSettings(QList<QString>& featureSettingsKeys, const AFCSettings& settings, bool force);
     void trackerDeviceChange(int deviceIndex);
     void trackedDeviceChange(int deviceIndex);
-    void removeTrackerFeatureReferences();
+    void removeTrackerFeatureReference();
     void removeTrackedFeatureReferences();
 
 private slots:
diff --git a/plugins/feature/afc/afcgui.cpp b/plugins/feature/afc/afcgui.cpp
index d2ac55ab4..c33552469 100644
--- a/plugins/feature/afc/afcgui.cpp
+++ b/plugins/feature/afc/afcgui.cpp
@@ -362,7 +362,8 @@ void AFCGUI::on_trackedDevice_currentIndexChanged(int index)
 
 void AFCGUI::on_devicesApply_clicked()
 {
-
+    AFC::MsgDevicesApply *msg = AFC::MsgDevicesApply::create();
+    m_afc->getInputMessageQueue()->push(msg);
 }
 
 void AFCGUI::on_targetPeriod_valueChanged(int value)
diff --git a/plugins/feature/afc/afcworker.cpp b/plugins/feature/afc/afcworker.cpp
index f0decea34..6d6c2aec4 100644
--- a/plugins/feature/afc/afcworker.cpp
+++ b/plugins/feature/afc/afcworker.cpp
@@ -119,12 +119,14 @@ bool AFCWorker::handleMessage(const Message& cmd)
     }
     else if (MsgDeviceTrack::match(cmd))
     {
+        qDebug() << "AFCWorker::handleMessage: MsgDeviceTrack";
         QMutexLocker mutexLocker(&m_mutex);
         updateTarget();
         return true;
     }
     else if (MsgDevicesApply::match(cmd))
     {
+        qDebug() << "AFCWorker::handleMessage: MsgDevicesApply";
         QMutexLocker mutexLocker(&m_mutex);
         initTrackerDeviceSet(m_settings.m_trackerDeviceSetIndex);
         initTrackedDeviceSet(m_settings.m_trackedDeviceSetIndex);
@@ -294,6 +296,7 @@ void AFCWorker::processChannelSettings(
             if (trackerChannelOffset != m_trackerChannelOffset)
             {
                 qDebug("AFCWorker::processChannelSettings: FreqTracker offset change: %d", trackerChannelOffset);
+                m_trackerChannelOffset = trackerChannelOffset;
                 QMap<ChannelAPI*, ChannelTracking>::iterator it = m_channelsMap.begin();
 
                 for (; it != m_channelsMap.end(); ++it)
@@ -308,8 +311,6 @@ void AFCWorker::processChannelSettings(
                         m_channelsMap.erase(it);
                     }
                 }
-
-                m_trackerChannelOffset = trackerChannelOffset;
             }
         }
         else if (m_channelsMap.contains(const_cast<ChannelAPI*>(channelAPI)))