diff --git a/plugins/samplesource/airspy/airspygui.cpp b/plugins/samplesource/airspy/airspygui.cpp
index 60b54b2fc..ad55b1345 100644
--- a/plugins/samplesource/airspy/airspygui.cpp
+++ b/plugins/samplesource/airspy/airspygui.cpp
@@ -46,7 +46,7 @@ AirspyGui::AirspyGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new AirspyInput();
+	m_sampleSource = new AirspyInput(m_pluginAPI);
 	m_rates = ((AirspyInput*) m_sampleSource)->getSampleRates();
 	displaySampleRates();
 	connect(m_sampleSource->getOutputMessageQueueToGUI(), SIGNAL(messageEnqueued()), this, SLOT(handleSourceMessages()));
diff --git a/plugins/samplesource/airspy/airspyinput.cpp b/plugins/samplesource/airspy/airspyinput.cpp
index d0ad423bf..9811a2c63 100644
--- a/plugins/samplesource/airspy/airspyinput.cpp
+++ b/plugins/samplesource/airspy/airspyinput.cpp
@@ -20,6 +20,7 @@
 
 #include "airspygui.h"
 #include "airspyinput.h"
+#include "plugin/pluginapi.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
 #include "airspysettings.h"
@@ -28,7 +29,8 @@
 MESSAGE_CLASS_DEFINITION(AirspyInput::MsgConfigureAirspy, Message)
 MESSAGE_CLASS_DEFINITION(AirspyInput::MsgReportAirspy, Message)
 
-AirspyInput::AirspyInput() :
+AirspyInput::AirspyInput(PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_settings(),
 	m_dev(0),
 	m_airspyThread(0),
@@ -449,7 +451,7 @@ bool AirspyInput::applySettings(const AirspySettings& settings, bool force)
 	{
 		int sampleRate = devSampleRate/(1<<m_settings.m_log2Decim);
 		DSPSignalNotification *notif = new DSPSignalNotification(sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
+		m_pluginAPI->getDeviceInputMessageQueue()->push(notif);
 	}
 
 	return true;
diff --git a/plugins/samplesource/airspy/airspyinput.h b/plugins/samplesource/airspy/airspyinput.h
index 2f2527c1c..237a79de8 100644
--- a/plugins/samplesource/airspy/airspyinput.h
+++ b/plugins/samplesource/airspy/airspyinput.h
@@ -22,6 +22,7 @@
 #include <libairspy/airspy.h>
 #include <QString>
 
+class PluginAPI;
 class AirspyThread;
 
 class AirspyInput : public SampleSource {
@@ -66,7 +67,7 @@ public:
 		{ }
 	};
 
-	AirspyInput();
+	AirspyInput(PluginAPI *pluginAPI);
 	virtual ~AirspyInput();
 
 	virtual bool init(const Message& message);
@@ -85,6 +86,7 @@ private:
 	struct airspy_device *open_airspy_from_sequence(int sequence);
 	void setCenterFrequency(quint64 freq);
 
+	PluginAPI *m_pluginAPI;
 	QMutex m_mutex;
 	AirspySettings m_settings;
 	struct airspy_device* m_dev;
diff --git a/plugins/samplesource/bladerf/bladerfgui.cpp b/plugins/samplesource/bladerf/bladerfgui.cpp
index d97c4b8c0..879cc7c23 100644
--- a/plugins/samplesource/bladerf/bladerfgui.cpp
+++ b/plugins/samplesource/bladerf/bladerfgui.cpp
@@ -59,7 +59,7 @@ BladerfGui::BladerfGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new BladerfInput();
+	m_sampleSource = new BladerfInput(m_pluginAPI);
 	DSPEngine::instance()->setSource(m_sampleSource);
 
 	char recFileNameCStr[30];
diff --git a/plugins/samplesource/bladerf/bladerfinput.cpp b/plugins/samplesource/bladerf/bladerfinput.cpp
index 18b252aea..f8c66328a 100644
--- a/plugins/samplesource/bladerf/bladerfinput.cpp
+++ b/plugins/samplesource/bladerf/bladerfinput.cpp
@@ -18,6 +18,7 @@
 #include <errno.h>
 #include <QDebug>
 
+#include "plugin/pluginapi.h"
 #include "util/simpleserializer.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
@@ -28,7 +29,8 @@
 MESSAGE_CLASS_DEFINITION(BladerfInput::MsgConfigureBladerf, Message)
 MESSAGE_CLASS_DEFINITION(BladerfInput::MsgReportBladerf, Message)
 
-BladerfInput::BladerfInput() :
+BladerfInput::BladerfInput(PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_settings(),
 	m_dev(0),
 	m_bladerfThread(0),
@@ -413,7 +415,7 @@ bool BladerfInput::applySettings(const BladeRFSettings& settings, bool force)
 	{
 		int sampleRate = m_settings.m_devSampleRate/(1<<m_settings.m_log2Decim);
 		DSPSignalNotification *notif = new DSPSignalNotification(sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
+		m_pluginAPI->getDeviceInputMessageQueue()->push(notif);
 	}
 
 	qDebug() << "BladerfInput::applySettings: center freq: " << m_settings.m_centerFrequency << " Hz"
diff --git a/plugins/samplesource/bladerf/bladerfinput.h b/plugins/samplesource/bladerf/bladerfinput.h
index 60f6eac91..99c47d8af 100644
--- a/plugins/samplesource/bladerf/bladerfinput.h
+++ b/plugins/samplesource/bladerf/bladerfinput.h
@@ -22,6 +22,7 @@
 #include <libbladeRF.h>
 #include <QString>
 
+class PluginAPI;
 class BladerfThread;
 
 class BladerfInput : public SampleSource {
@@ -63,7 +64,7 @@ public:
 		{ }
 	};
 
-	BladerfInput();
+	BladerfInput(PluginAPI *pluginAPI);
 	virtual ~BladerfInput();
 
 	virtual bool init(const Message& message);
@@ -81,6 +82,7 @@ private:
 	bladerf_lna_gain getLnaGain(int lnaGain);
 	struct bladerf *open_bladerf_from_serial(const char *serial);
 
+	PluginAPI *m_pluginAPI;
 	QMutex m_mutex;
 	BladeRFSettings m_settings;
 	struct bladerf* m_dev;
diff --git a/plugins/samplesource/fcdpro/fcdprogui.cpp b/plugins/samplesource/fcdpro/fcdprogui.cpp
index aeecfb44f..c9561f069 100644
--- a/plugins/samplesource/fcdpro/fcdprogui.cpp
+++ b/plugins/samplesource/fcdpro/fcdprogui.cpp
@@ -140,7 +140,7 @@ FCDProGui::FCDProGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new FCDProInput();
+	m_sampleSource = new FCDProInput(m_pluginAPI);
 	DSPEngine::instance()->setSource(m_sampleSource);
 
     char recFileNameCStr[30];
diff --git a/plugins/samplesource/fcdpro/fcdproinput.cpp b/plugins/samplesource/fcdpro/fcdproinput.cpp
index 750f54318..0a499f80e 100644
--- a/plugins/samplesource/fcdpro/fcdproinput.cpp
+++ b/plugins/samplesource/fcdpro/fcdproinput.cpp
@@ -20,6 +20,8 @@
 #include <QDebug>
 #include <string.h>
 #include <errno.h>
+
+#include "plugin/pluginapi.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
 #include "fcdproinput.h"
@@ -31,7 +33,8 @@
 
 MESSAGE_CLASS_DEFINITION(FCDProInput::MsgConfigureFCD, Message)
 
-FCDProInput::FCDProInput() :
+FCDProInput::FCDProInput(PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_dev(0),
 	m_settings(),
 	m_FCDThread(0),
@@ -344,7 +347,7 @@ void FCDProInput::applySettings(const FCDProSettings& settings, bool force)
     if (signalChange)
     {
 		DSPSignalNotification *notif = new DSPSignalNotification(fcd_traits<Pro>::sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
+		m_pluginAPI->getDeviceInputMessageQueue()->push(notif);
     }
 }
 
diff --git a/plugins/samplesource/fcdpro/fcdproinput.h b/plugins/samplesource/fcdpro/fcdproinput.h
index 9c8d7573a..787db25db 100644
--- a/plugins/samplesource/fcdpro/fcdproinput.h
+++ b/plugins/samplesource/fcdpro/fcdproinput.h
@@ -29,6 +29,7 @@ struct fcd_buffer {
 	std::size_t length;
 };
 
+class PluginAPI;
 class FCDProThread;
 
 class FCDProInput : public SampleSource {
@@ -53,7 +54,7 @@ public:
 		{ }
 	};
 
-	FCDProInput();
+	FCDProInput(PluginAPI *pluginAPI);
 	virtual ~FCDProInput();
 
 	virtual bool init(const Message& cmd);
@@ -89,6 +90,7 @@ private:
 	void applySettings(const FCDProSettings& settings, bool force);
 	void set_lo_ppm();
 
+	PluginAPI *m_pluginAPI;
 	hid_device *m_dev;
 	QMutex m_mutex;
 	FCDProSettings m_settings;
diff --git a/plugins/samplesource/fcdproplus/fcdproplusgui.cpp b/plugins/samplesource/fcdproplus/fcdproplusgui.cpp
index c4dec99bb..c20cabcfb 100644
--- a/plugins/samplesource/fcdproplus/fcdproplusgui.cpp
+++ b/plugins/samplesource/fcdproplus/fcdproplusgui.cpp
@@ -58,7 +58,7 @@ FCDProPlusGui::FCDProPlusGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new FCDProPlusInput();
+	m_sampleSource = new FCDProPlusInput(m_pluginAPI);
 	DSPEngine::instance()->setSource(m_sampleSource);
 
 	char recFileNameCStr[30];
diff --git a/plugins/samplesource/fcdproplus/fcdproplusinput.cpp b/plugins/samplesource/fcdproplus/fcdproplusinput.cpp
index a8fd7acb2..d213ed4bc 100644
--- a/plugins/samplesource/fcdproplus/fcdproplusinput.cpp
+++ b/plugins/samplesource/fcdproplus/fcdproplusinput.cpp
@@ -19,6 +19,8 @@
 #include <QDebug>
 #include <string.h>
 #include <errno.h>
+
+#include "plugin/pluginapi.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
 #include "fcdproplusinput.h"
@@ -30,7 +32,8 @@
 
 MESSAGE_CLASS_DEFINITION(FCDProPlusInput::MsgConfigureFCD, Message)
 
-FCDProPlusInput::FCDProPlusInput() :
+FCDProPlusInput::FCDProPlusInput(PluginAPI *pluginAPI) :
+    m_pluginApi(pluginAPI),
 	m_dev(0),
 	m_settings(),
 	m_FCDThread(0),
@@ -177,7 +180,7 @@ void FCDProPlusInput::applySettings(const FCDProPlusSettings& settings, bool for
 			set_bias_t(settings.m_biasT);
 		}
 	}
-    
+
 	if ((m_settings.m_mixGain != settings.m_mixGain) || force)
 	{
 		m_settings.m_mixGain = settings.m_mixGain;
@@ -243,7 +246,8 @@ void FCDProPlusInput::applySettings(const FCDProPlusSettings& settings, bool for
 	if (signalChange)
     {
 		DSPSignalNotification *notif = new DSPSignalNotification(fcd_traits<ProPlus>::sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
+		m_pluginApi->getDeviceInputMessageQueue()->push(notif);
+		//DSPEngine::instance()->getInputMessageQueue()->push(notif);
     }
 }
 
diff --git a/plugins/samplesource/fcdproplus/fcdproplusinput.h b/plugins/samplesource/fcdproplus/fcdproplusinput.h
index f4af3db1e..ad86290db 100644
--- a/plugins/samplesource/fcdproplus/fcdproplusinput.h
+++ b/plugins/samplesource/fcdproplus/fcdproplusinput.h
@@ -28,6 +28,7 @@ struct fcd_buffer {
 	std::size_t length;
 };
 
+class PluginAPI;
 class FCDProPlusThread;
 
 class FCDProPlusInput : public SampleSource {
@@ -52,7 +53,7 @@ public:
 		{ }
 	};
 
-	FCDProPlusInput();
+	FCDProPlusInput(PluginAPI *pluginAPI);
 	virtual ~FCDProPlusInput();
 
 	virtual bool init(const Message& cmd);
@@ -77,6 +78,7 @@ public:
 private:
 	void applySettings(const FCDProPlusSettings& settings, bool force);
 
+	PluginAPI *m_pluginApi;
 	hid_device *m_dev;
 	QMutex m_mutex;
 	FCDProPlusSettings m_settings;
diff --git a/plugins/samplesource/hackrf/hackrfgui.cpp b/plugins/samplesource/hackrf/hackrfgui.cpp
index 5b489fd54..cd1624db4 100644
--- a/plugins/samplesource/hackrf/hackrfgui.cpp
+++ b/plugins/samplesource/hackrf/hackrfgui.cpp
@@ -46,7 +46,7 @@ HackRFGui::HackRFGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new HackRFInput();
+	m_sampleSource = new HackRFInput(m_pluginAPI);
 
 	displaySampleRates();
 	displayBandwidths();
diff --git a/plugins/samplesource/hackrf/hackrfinput.cpp b/plugins/samplesource/hackrf/hackrfinput.cpp
index fefbb1084..7fe2fb7a3 100644
--- a/plugins/samplesource/hackrf/hackrfinput.cpp
+++ b/plugins/samplesource/hackrf/hackrfinput.cpp
@@ -18,6 +18,7 @@
 #include <errno.h>
 #include <QDebug>
 
+#include "plugin/pluginapi.h"
 #include "util/simpleserializer.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
@@ -29,7 +30,8 @@
 MESSAGE_CLASS_DEFINITION(HackRFInput::MsgConfigureHackRF, Message)
 MESSAGE_CLASS_DEFINITION(HackRFInput::MsgReportHackRF, Message)
 
-HackRFInput::HackRFInput() :
+HackRFInput::HackRFInput(PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_settings(),
 	m_dev(0),
 	m_hackRFThread(0),
@@ -396,8 +398,7 @@ bool HackRFInput::applySettings(const HackRFSettings& settings, bool force)
 	{
 		int sampleRate = devSampleRate/(1<<m_settings.m_log2Decim);
 		DSPSignalNotification *notif = new DSPSignalNotification(sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
-		//getOutputMessageQueue()->push(notif);
+		m_pluginAPI->getDeviceInputMessageQueue()->push(notif);
 	}
 
 	return true;
diff --git a/plugins/samplesource/hackrf/hackrfinput.h b/plugins/samplesource/hackrf/hackrfinput.h
index 5349aec6a..24d2bfc6c 100644
--- a/plugins/samplesource/hackrf/hackrfinput.h
+++ b/plugins/samplesource/hackrf/hackrfinput.h
@@ -22,6 +22,7 @@
 #include "hackrfsettings.h"
 #include <QString>
 
+class PluginAPI;
 class HackRFThread;
 
 class HackRFInput : public SampleSource {
@@ -64,7 +65,7 @@ public:
 		{ }
 	};
 
-	HackRFInput();
+	HackRFInput(PluginAPI *pluginAPI);
 	virtual ~HackRFInput();
 
 	virtual bool init(const Message& message);
@@ -82,6 +83,7 @@ private:
 	hackrf_device *open_hackrf_from_sequence(int sequence);
 	void setCenterFrequency(quint64 freq);
 
+	PluginAPI *m_pluginAPI;
 	QMutex m_mutex;
 	HackRFSettings m_settings;
 	struct hackrf_device* m_dev;
diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
index fb5bdde7c..9a5750b22 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
@@ -51,7 +51,7 @@ RTLSDRGui::RTLSDRGui(PluginAPI* pluginAPI, QWidget* parent) :
 
 	displaySettings();
 
-	m_sampleSource = new RTLSDRInput();
+	m_sampleSource = new RTLSDRInput(m_pluginAPI);
 	connect(m_sampleSource->getOutputMessageQueueToGUI(), SIGNAL(messageEnqueued()), this, SLOT(handleSourceMessages()));
 	DSPEngine::instance()->setSource(m_sampleSource);
 
diff --git a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
index a730f1fe3..f162f82e4 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
@@ -21,13 +21,15 @@
 #include "rtlsdrinput.h"
 #include "rtlsdrthread.h"
 #include "rtlsdrgui.h"
+#include "plugin/pluginapi.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
 
 MESSAGE_CLASS_DEFINITION(RTLSDRInput::MsgConfigureRTLSDR, Message)
 MESSAGE_CLASS_DEFINITION(RTLSDRInput::MsgReportRTLSDR, Message)
 
-RTLSDRInput::RTLSDRInput() :
+RTLSDRInput::RTLSDRInput(PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_settings(),
 	m_dev(0),
 	m_rtlSDRThread(0),
@@ -230,7 +232,7 @@ bool RTLSDRInput::applySettings(const RTLSDRSettings& settings, bool force)
 	if ((m_settings.m_devSampleRate != settings.m_devSampleRate) || force)
 	{
         forwardChange = true;
-        
+
 		if(m_dev != 0)
 		{
 			if( rtlsdr_set_sample_rate(m_dev, settings.m_devSampleRate) < 0)
@@ -264,7 +266,7 @@ bool RTLSDRInput::applySettings(const RTLSDRSettings& settings, bool force)
 	if ((m_settings.m_log2Decim != settings.m_log2Decim) || force)
 	{
         forwardChange = true;
-        
+
 		if(m_dev != 0)
 		{
 			m_settings.m_log2Decim = settings.m_log2Decim;
@@ -352,7 +354,7 @@ bool RTLSDRInput::applySettings(const RTLSDRSettings& settings, bool force)
 			qDebug("rtlsdr_set_center_freq(%lld) failed", m_settings.m_centerFrequency);
 		}
 	}*/
-    
+
 	if ((m_settings.m_dcBlock != settings.m_dcBlock) || force)
 	{
 		m_settings.m_dcBlock = settings.m_dcBlock;
@@ -369,7 +371,7 @@ bool RTLSDRInput::applySettings(const RTLSDRSettings& settings, bool force)
     {
 		int sampleRate = m_settings.m_devSampleRate/(1<<m_settings.m_log2Decim);
 		DSPSignalNotification *notif = new DSPSignalNotification(sampleRate, m_settings.m_centerFrequency);
-		DSPEngine::instance()->getInputMessageQueue()->push(notif);
+		m_pluginAPI->getDeviceInputMessageQueue()->push(notif);
     }
 
 	return true;
diff --git a/plugins/samplesource/rtlsdr/rtlsdrinput.h b/plugins/samplesource/rtlsdr/rtlsdrinput.h
index 732282e9e..c0f813756 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrinput.h
+++ b/plugins/samplesource/rtlsdr/rtlsdrinput.h
@@ -23,6 +23,7 @@
 #include <rtl-sdr.h>
 #include <QString>
 
+class PluginAPI;
 class RTLSDRThread;
 
 class RTLSDRInput : public SampleSource {
@@ -67,7 +68,7 @@ public:
 		{ }
 	};
 
-	RTLSDRInput();
+	RTLSDRInput(PluginAPI *pluginAPI);
 	virtual ~RTLSDRInput();
 
 	virtual bool init(const Message& message);
@@ -83,6 +84,7 @@ public:
 	void set_ds_mode(int on);
 
 private:
+	PluginAPI *m_pluginAPI;
 	QMutex m_mutex;
 	RTLSDRSettings m_settings;
 	rtlsdr_dev_t* m_dev;
diff --git a/plugins/samplesource/sdrdaemon/sdrdaemongui.cpp b/plugins/samplesource/sdrdaemon/sdrdaemongui.cpp
index c760b14d9..7c96e84f8 100644
--- a/plugins/samplesource/sdrdaemon/sdrdaemongui.cpp
+++ b/plugins/samplesource/sdrdaemon/sdrdaemongui.cpp
@@ -88,7 +88,7 @@ SDRdaemonGui::SDRdaemonGui(PluginAPI* pluginAPI, QWidget* parent) :
 	m_statusTimer.start(500);
 	connect(&(m_pluginAPI->getMainWindow()->getMasterTimer()), SIGNAL(timeout()), this, SLOT(tick()));
 
-	m_sampleSource = new SDRdaemonInput(m_pluginAPI->getMainWindow()->getMasterTimer());
+	m_sampleSource = new SDRdaemonInput(m_pluginAPI->getMainWindow()->getMasterTimer(), m_pluginAPI);
 	connect(m_sampleSource->getOutputMessageQueueToGUI(), SIGNAL(messageEnqueued()), this, SLOT(handleSourceMessages()));
 	DSPEngine::instance()->setSource(m_sampleSource);
 
diff --git a/plugins/samplesource/sdrdaemon/sdrdaemoninput.cpp b/plugins/samplesource/sdrdaemon/sdrdaemoninput.cpp
index a511e1865..6ef78eaef 100644
--- a/plugins/samplesource/sdrdaemon/sdrdaemoninput.cpp
+++ b/plugins/samplesource/sdrdaemon/sdrdaemoninput.cpp
@@ -18,6 +18,7 @@
 #include <errno.h>
 #include <QDebug>
 
+#include "plugin/pluginapi.h"
 #include "util/simpleserializer.h"
 #include "dsp/dspcommands.h"
 #include "dsp/dspengine.h"
@@ -37,7 +38,8 @@ MESSAGE_CLASS_DEFINITION(SDRdaemonInput::MsgReportSDRdaemonAcquisition, Message)
 MESSAGE_CLASS_DEFINITION(SDRdaemonInput::MsgReportSDRdaemonStreamData, Message)
 MESSAGE_CLASS_DEFINITION(SDRdaemonInput::MsgReportSDRdaemonStreamTiming, Message)
 
-SDRdaemonInput::SDRdaemonInput(const QTimer& masterTimer) :
+SDRdaemonInput::SDRdaemonInput(const QTimer& masterTimer, PluginAPI *pluginAPI) :
+    m_pluginAPI(pluginAPI),
 	m_address("127.0.0.1"),
 	m_port(9090),
 	m_SDRdaemonUDPHandler(0),
diff --git a/plugins/samplesource/sdrdaemon/sdrdaemoninput.h b/plugins/samplesource/sdrdaemon/sdrdaemoninput.h
index 4a8236e70..6aa1b6a72 100644
--- a/plugins/samplesource/sdrdaemon/sdrdaemoninput.h
+++ b/plugins/samplesource/sdrdaemon/sdrdaemoninput.h
@@ -24,6 +24,7 @@
 #include <iostream>
 #include <stdint.h>
 
+class PluginAPI;
 class SDRdaemonUDPHandler;
 
 class SDRdaemonInput : public SampleSource {
@@ -273,7 +274,7 @@ public:
 		{ }
 	};
 
-	SDRdaemonInput(const QTimer& masterTimer);
+	SDRdaemonInput(const QTimer& masterTimer, PluginAPI *pluginAPI);
 	virtual ~SDRdaemonInput();
 
 	virtual bool init(const Message& message);
@@ -289,6 +290,7 @@ public:
 	virtual bool handleMessage(const Message& message);
 
 private:
+	PluginAPI *m_pluginAPI;
 	QMutex m_mutex;
 	QString m_address;
 	quint16 m_port;
diff --git a/sdrbase/dsp/dspengine.cpp b/sdrbase/dsp/dspengine.cpp
index f1b2b7e5d..5681b2fb0 100644
--- a/sdrbase/dsp/dspengine.cpp
+++ b/sdrbase/dsp/dspengine.cpp
@@ -49,11 +49,6 @@ MessageQueue* DSPEngine::getInputMessageQueue(uint deviceIndex)
 	return m_deviceEngines[deviceIndex]->getInputMessageQueue();
 }
 
-MessageQueue* DSPEngine::getOutputMessageQueue(uint deviceIndex)
-{
-	return m_deviceEngines[deviceIndex]->getOutputMessageQueue();
-}
-
 void DSPEngine::stopAllAcquisitions()
 {
     std::vector<DSPDeviceEngine*>::iterator it = m_deviceEngines.begin();
diff --git a/sdrbase/dsp/dspengine.h b/sdrbase/dsp/dspengine.h
index 03b887542..fc7004fd6 100644
--- a/sdrbase/dsp/dspengine.h
+++ b/sdrbase/dsp/dspengine.h
@@ -39,7 +39,6 @@ public:
 	static DSPEngine *instance();
 
 	MessageQueue* getInputMessageQueue(uint deviceIndex = 0);
-	MessageQueue* getOutputMessageQueue(uint deviceIndex = 0);
 
 	uint getAudioSampleRate() const { return m_audioSampleRate; }
 
diff --git a/sdrbase/mainwindow.cpp b/sdrbase/mainwindow.cpp
index f06d1e67e..a007632b3 100644
--- a/sdrbase/mainwindow.cpp
+++ b/sdrbase/mainwindow.cpp
@@ -276,11 +276,6 @@ void MainWindow::closeEvent(QCloseEvent*)
 {
 }
 
-void MainWindow::updateCenterFreqDisplay()
-{
-	m_deviceUIs.back()->m_spectrum->setCenterFrequency(m_centerFrequency);
-}
-
 void MainWindow::updatePresetControls()
 {
 	ui->presetTree->resizeColumnToContents(0);
@@ -334,7 +329,6 @@ QTreeWidgetItem* MainWindow::addPresetToTree(const Preset* preset)
 
 void MainWindow::applySettings()
 {
-	updateCenterFreqDisplay();
 }
 
 void MainWindow::handleMessages()
diff --git a/sdrbase/mainwindow.h b/sdrbase/mainwindow.h
index bb6b10586..c83fb851c 100644
--- a/sdrbase/mainwindow.h
+++ b/sdrbase/mainwindow.h
@@ -122,7 +122,6 @@ private:
 
 	void createStatusBar();
 	void closeEvent(QCloseEvent*);
-	void updateCenterFreqDisplay();
 	void updatePresetControls();
 	QTreeWidgetItem* addPresetToTree(const Preset* preset);
 	void applySettings();