diff --git a/include/ComboBoxModel.h b/include/ComboBoxModel.h
index e90d804e2df..a6df2964f4f 100644
--- a/include/ComboBoxModel.h
+++ b/include/ComboBoxModel.h
@@ -30,11 +30,12 @@
 #include <vector>
 
 #include "AutomatableModel.h"
-#include "embed.h"
 
 namespace lmms
 {
 
+class PixmapLoader;
+
 class LMMS_EXPORT ComboBoxModel : public IntModel
 {
 	Q_OBJECT
@@ -42,19 +43,15 @@ class LMMS_EXPORT ComboBoxModel : public IntModel
 public:
 	ComboBoxModel( Model* parent = nullptr,
 					const QString& displayName = QString(),
-					bool isDefaultConstructed = false ) :
-		IntModel( 0, 0, 0, parent, displayName, isDefaultConstructed )
-	{
-	}
+					bool isDefaultConstructed = false );
 
-	~ComboBoxModel() override
-	{
-		clear();
-	}
+	~ComboBoxModel() override;
 
-	void addItem( QString item, std::unique_ptr<PixmapLoader> loader = nullptr );
+	void addItem( QString item );
+	void addItem( QString item, std::unique_ptr<PixmapLoader> loader );
 
-	void replaceItem(std::size_t index, QString item, std::unique_ptr<PixmapLoader> loader = nullptr);
+	void replaceItem(std::size_t index, QString item);
+	void replaceItem(std::size_t index, QString item, std::unique_ptr<PixmapLoader> loader );
 
 	void clear();
 
diff --git a/include/MixerView.h b/include/MixerView.h
index 2bb5ed4170f..d7a04ee2638 100644
--- a/include/MixerView.h
+++ b/include/MixerView.h
@@ -34,7 +34,6 @@
 #include "Engine.h"
 #include "Fader.h"
 #include "PixmapButton.h"
-#include "embed.h"
 #include "EffectRackView.h"
 
 class QButtonGroup;
diff --git a/plugins/DualFilter/DualFilterControlDialog.cpp b/plugins/DualFilter/DualFilterControlDialog.cpp
index d316e337213..79bbedbb6c0 100644
--- a/plugins/DualFilter/DualFilterControlDialog.cpp
+++ b/plugins/DualFilter/DualFilterControlDialog.cpp
@@ -24,6 +24,7 @@
  */
 
 
+#include "embed.h"
 #include "DualFilterControlDialog.h"
 #include "DualFilterControls.h"
 #include "Knob.h"
diff --git a/plugins/LadspaEffect/cmt/CMakeLists.txt b/plugins/LadspaEffect/cmt/CMakeLists.txt
index 75dba319d6c..2e5b377f35d 100644
--- a/plugins/LadspaEffect/cmt/CMakeLists.txt
+++ b/plugins/LadspaEffect/cmt/CMakeLists.txt
@@ -5,6 +5,7 @@ ADD_LIBRARY(cmt MODULE ${SOURCES})
 INSTALL(TARGETS cmt LIBRARY DESTINATION "${PLUGIN_DIR}/ladspa")
 
 SET_TARGET_PROPERTIES(cmt PROPERTIES PREFIX "")
+SET_TARGET_PROPERTIES(cmt PROPERTIES UNITY_BUILD OFF)
 target_compile_options(cmt PRIVATE -Wall -O3 -fno-strict-aliasing)
 
 if(LMMS_BUILD_WIN32)
diff --git a/plugins/MidiExport/MidiExport.cpp b/plugins/MidiExport/MidiExport.cpp
index df968e36ab3..876d125f3a8 100644
--- a/plugins/MidiExport/MidiExport.cpp
+++ b/plugins/MidiExport/MidiExport.cpp
@@ -27,6 +27,8 @@
 
 #include "MidiExport.h"
 
+#include <QDataStream>
+
 #include "TrackContainer.h"
 #include "DataFile.h"
 #include "InstrumentTrack.h"
diff --git a/plugins/MidiImport/portsmf/algrd_internal.h b/plugins/MidiImport/portsmf/algrd_internal.h
index 56a9cdc46af..7f3126decb9 100644
--- a/plugins/MidiImport/portsmf/algrd_internal.h
+++ b/plugins/MidiImport/portsmf/algrd_internal.h
@@ -1,4 +1,5 @@
 /* algread_internal.h -- interface between allegro.cpp and allegrord.cpp */
+#pragma once
 
 #include "allegro.h"
 
diff --git a/plugins/MidiImport/portsmf/algsmfrd_internal.h b/plugins/MidiImport/portsmf/algsmfrd_internal.h
index 65e7ac8744c..23986308d56 100644
--- a/plugins/MidiImport/portsmf/algsmfrd_internal.h
+++ b/plugins/MidiImport/portsmf/algsmfrd_internal.h
@@ -1,4 +1,5 @@
 /* algsmfrd_internal.h -- interface from allegrosmfrd.cpp to allegro.cpp */
+#pragma once
 
 #include "allegro.h"
 
diff --git a/plugins/MidiImport/portsmf/mfmidi.h b/plugins/MidiImport/portsmf/mfmidi.h
index f1972124635..2aec6a4d914 100644
--- a/plugins/MidiImport/portsmf/mfmidi.h
+++ b/plugins/MidiImport/portsmf/mfmidi.h
@@ -1,3 +1,4 @@
+#pragma once
 #include <cstddef>
 
 #define NOTEOFF 0x80
diff --git a/plugins/MidiImport/portsmf/strparse.h b/plugins/MidiImport/portsmf/strparse.h
index 046b1ddd381..1bac2a6b6aa 100644
--- a/plugins/MidiImport/portsmf/strparse.h
+++ b/plugins/MidiImport/portsmf/strparse.h
@@ -1,4 +1,5 @@
 // strparse.h -- header for String_parse class
+#pragma once
 
 class String_parse {
 public:
diff --git a/plugins/MidiImport/portsmf/trace.h b/plugins/MidiImport/portsmf/trace.h
index 52a23a69b82..7e94f59bbd0 100644
--- a/plugins/MidiImport/portsmf/trace.h
+++ b/plugins/MidiImport/portsmf/trace.h
@@ -1,2 +1,3 @@
+#pragma once
 void trace(char *format, ...);
 
diff --git a/plugins/Monstro/Monstro.cpp b/plugins/Monstro/Monstro.cpp
index 2201e4ed90b..3deda58f19f 100644
--- a/plugins/Monstro/Monstro.cpp
+++ b/plugins/Monstro/Monstro.cpp
@@ -62,6 +62,32 @@ Plugin::Descriptor PLUGIN_EXPORT monstro_plugin_descriptor =
 }
 
 
+//
+//	UI Macros
+//
+
+#define makeknob( name, x, y, hint, unit, oname ) 		\
+	name = new Knob( KnobType::Styled, view ); 				\
+	name ->move( x, y );								\
+	name ->setHintText( hint, unit );             \
+	name ->setObjectName( oname );						\
+	name ->setFixedSize( 20, 20 );
+
+#define maketsknob( name, x, y, hint, unit, oname ) 		\
+	name = new TempoSyncKnob( KnobType::Styled, view ); 				\
+	name ->move( x, y );								\
+	name ->setHintText( hint, unit );		\
+	name ->setObjectName( oname );						\
+	name ->setFixedSize( 20, 20 );
+
+#define maketinyled( name, x, y, ttip ) \
+	name = new PixmapButton( view, nullptr ); 	\
+	name -> setCheckable( true );			\
+	name -> move( x, y );					\
+	name -> setActiveGraphic( PLUGIN_NAME::getIconPixmap( "tinyled_on" ) ); \
+	name -> setInactiveGraphic( PLUGIN_NAME::getIconPixmap( "tinyled_off" ) ); \
+	name->setToolTip(ttip);
+
 
 
 MonstroSynth::MonstroSynth( MonstroInstrument * _i, NotePlayHandle * _nph ) :
diff --git a/plugins/Monstro/Monstro.h b/plugins/Monstro/Monstro.h
index 21efedaf314..c42218d3f6c 100644
--- a/plugins/Monstro/Monstro.h
+++ b/plugins/Monstro/Monstro.h
@@ -38,32 +38,6 @@
 #include "lmms_math.h"
 #include "BandLimitedWave.h"
 
-//
-//	UI Macros
-//
-
-#define makeknob( name, x, y, hint, unit, oname ) 		\
-	name = new Knob( KnobType::Styled, view ); 				\
-	name ->move( x, y );								\
-	name ->setHintText( hint, unit );             \
-	name ->setObjectName( oname );						\
-	name ->setFixedSize( 20, 20 );
-
-#define maketsknob( name, x, y, hint, unit, oname ) 		\
-	name = new TempoSyncKnob( KnobType::Styled, view ); 				\
-	name ->move( x, y );								\
-	name ->setHintText( hint, unit );		\
-	name ->setObjectName( oname );						\
-	name ->setFixedSize( 20, 20 );
-
-#define maketinyled( name, x, y, ttip ) \
-	name = new PixmapButton( view, nullptr ); 	\
-	name -> setCheckable( true );			\
-	name -> move( x, y );					\
-	name -> setActiveGraphic( PLUGIN_NAME::getIconPixmap( "tinyled_on" ) ); \
-	name -> setInactiveGraphic( PLUGIN_NAME::getIconPixmap( "tinyled_off" ) ); \
-	name->setToolTip(ttip);
-
 namespace lmms
 {
 
diff --git a/plugins/ReverbSC/base.h b/plugins/ReverbSC/base.h
index 74c535cdc1b..b8fba5fa29a 100644
--- a/plugins/ReverbSC/base.h
+++ b/plugins/ReverbSC/base.h
@@ -1,3 +1,4 @@
+#pragma once
 #include <stdint.h>
 #include <stdio.h>
 
diff --git a/plugins/ReverbSC/dcblock.h b/plugins/ReverbSC/dcblock.h
index d98d5856654..6b50ba174f5 100644
--- a/plugins/ReverbSC/dcblock.h
+++ b/plugins/ReverbSC/dcblock.h
@@ -1,3 +1,4 @@
+#pragma once
 typedef struct {
     SPFLOAT gg;
     SPFLOAT outputs;
diff --git a/plugins/ReverbSC/revsc.h b/plugins/ReverbSC/revsc.h
index 7bf07e7bfb9..b65f8b84804 100644
--- a/plugins/ReverbSC/revsc.h
+++ b/plugins/ReverbSC/revsc.h
@@ -1,3 +1,4 @@
+#pragma once
 typedef struct {
     int writePos;
     int bufferSize;
diff --git a/plugins/SpectrumAnalyzer/SaControls.h b/plugins/SpectrumAnalyzer/SaControls.h
index 48d8ee96ea9..4225f80b8aa 100644
--- a/plugins/SpectrumAnalyzer/SaControls.h
+++ b/plugins/SpectrumAnalyzer/SaControls.h
@@ -25,6 +25,8 @@
 #ifndef SACONTROLS_H
 #define SACONTROLS_H
 
+#include <QColor>
+
 #include "ComboBoxModel.h"
 #include "EffectControls.h"
 
diff --git a/plugins/SpectrumAnalyzer/SaControlsDialog.cpp b/plugins/SpectrumAnalyzer/SaControlsDialog.cpp
index eb09c793a9f..30b4367cc68 100644
--- a/plugins/SpectrumAnalyzer/SaControlsDialog.cpp
+++ b/plugins/SpectrumAnalyzer/SaControlsDialog.cpp
@@ -30,6 +30,7 @@
 #include <QSplitter>
 #include <QWidget>
 
+#include "embed.h"
 #include "ComboBox.h"
 #include "ComboBoxModel.h"
 #include "Knob.h"
diff --git a/plugins/ZynAddSubFx/CMakeLists.txt b/plugins/ZynAddSubFx/CMakeLists.txt
index 3369a793865..7fd8133926a 100644
--- a/plugins/ZynAddSubFx/CMakeLists.txt
+++ b/plugins/ZynAddSubFx/CMakeLists.txt
@@ -23,9 +23,8 @@ if(NOT MSVC AND (LMMS_HOST_X86 OR LMMS_HOST_X86_64))
 	ADD_DEFINITIONS(-DASM_F2I_YES)
 endif()
 
-# build ZynAddSubFX with full optimizations
 if(NOT MSVC)
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2 -Wno-write-strings -Wno-deprecated-declarations -fpermissive")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-write-strings -Wno-deprecated-declarations -fpermissive")
 endif()
 
 IF("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU" AND NOT "${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS "6.0.0")
diff --git a/src/core/ComboBoxModel.cpp b/src/core/ComboBoxModel.cpp
index f1b1c6b2e0f..a8b880ca4a4 100644
--- a/src/core/ComboBoxModel.cpp
+++ b/src/core/ComboBoxModel.cpp
@@ -26,18 +26,41 @@
 
 #include <cassert>
 
+#include "embed.h"
+
 namespace lmms
 {
 
 using std::unique_ptr;
 using std::move;
 
+ComboBoxModel::ComboBoxModel(Model* parent, const QString& displayName, bool isDefaultConstructed)
+	:
+	IntModel( 0, 0, 0, parent, displayName, isDefaultConstructed )
+{
+}
+
+ComboBoxModel::~ComboBoxModel()
+{
+	clear();
+}
+
+void ComboBoxModel::addItem(QString item)
+{
+	addItem( item, nullptr );
+}
+
 void ComboBoxModel::addItem( QString item, unique_ptr<PixmapLoader> loader )
 {
 	m_items.emplace_back( move(item), move(loader) );
 	setRange( 0, m_items.size() - 1 );
 }
 
+void ComboBoxModel::replaceItem(std::size_t index, QString item)
+{
+	replaceItem(index, item, nullptr);
+}
+
 
 void ComboBoxModel::replaceItem(std::size_t index, QString item, unique_ptr<PixmapLoader> loader)
 {
diff --git a/src/gui/GuiApplication.cpp b/src/gui/GuiApplication.cpp
index 3370cbc6ebf..b1446e6a9fa 100644
--- a/src/gui/GuiApplication.cpp
+++ b/src/gui/GuiApplication.cpp
@@ -26,6 +26,7 @@
 
 #include "lmmsversion.h"
 
+#include "embed.h"
 #include "LmmsStyle.h"
 #include "LmmsPalette.h"
 
diff --git a/src/gui/LinkedModelGroupViews.cpp b/src/gui/LinkedModelGroupViews.cpp
index f77edcdb9de..3439e53db19 100644
--- a/src/gui/LinkedModelGroupViews.cpp
+++ b/src/gui/LinkedModelGroupViews.cpp
@@ -25,6 +25,7 @@
 #include "LinkedModelGroupViews.h"
 
 #include <QPushButton>
+#include "embed.h"
 #include "Controls.h"
 #include "ControlLayout.h"
 #include "LinkedModelGroups.h"
diff --git a/src/gui/MixerView.cpp b/src/gui/MixerView.cpp
index 018e72c2b20..20e495c60a2 100644
--- a/src/gui/MixerView.cpp
+++ b/src/gui/MixerView.cpp
@@ -33,6 +33,7 @@
 
 #include "lmms_math.h"
 
+#include "embed.h"
 #include "MixerView.h"
 #include "Knob.h"
 #include "MixerLine.h"
diff --git a/src/gui/clips/MidiClipView.cpp b/src/gui/clips/MidiClipView.cpp
index 151df8d3c3c..842ce7e4444 100644
--- a/src/gui/clips/MidiClipView.cpp
+++ b/src/gui/clips/MidiClipView.cpp
@@ -31,6 +31,7 @@
 #include <QMenu>
 #include <QPainter>
 
+#include "embed.h"
 #include "ConfigManager.h"
 #include "DeprecationHelper.h"
 #include "GuiApplication.h"
diff --git a/src/gui/clips/PatternClipView.cpp b/src/gui/clips/PatternClipView.cpp
index bf12440c722..c0af6067745 100644
--- a/src/gui/clips/PatternClipView.cpp
+++ b/src/gui/clips/PatternClipView.cpp
@@ -28,6 +28,7 @@
 #include <QMenu>
 #include <QPainter>
 
+#include "embed.h"
 #include "Engine.h"
 #include "GuiApplication.h"
 #include "MainWindow.h"
diff --git a/src/gui/instrument/InstrumentTuningView.cpp b/src/gui/instrument/InstrumentTuningView.cpp
index 355d7d18c73..d7a01893efe 100644
--- a/src/gui/instrument/InstrumentTuningView.cpp
+++ b/src/gui/instrument/InstrumentTuningView.cpp
@@ -30,6 +30,7 @@
 #include <QPixmap>
 #include <QVBoxLayout>
 
+#include "embed.h"
 #include "ComboBox.h"
 #include "GroupBox.h"
 #include "GuiApplication.h"
diff --git a/src/gui/tracks/InstrumentTrackView.cpp b/src/gui/tracks/InstrumentTrackView.cpp
index 87c0f044944..04d1628242c 100644
--- a/src/gui/tracks/InstrumentTrackView.cpp
+++ b/src/gui/tracks/InstrumentTrackView.cpp
@@ -31,6 +31,7 @@
 #include <QMdiSubWindow>
 #include <QMenu>
 
+#include "embed.h"
 #include "AudioEngine.h"
 #include "ConfigManager.h"
 #include "Engine.h"
diff --git a/src/gui/tracks/PatternTrackView.cpp b/src/gui/tracks/PatternTrackView.cpp
index be039ba79e5..1f1aa75eca2 100644
--- a/src/gui/tracks/PatternTrackView.cpp
+++ b/src/gui/tracks/PatternTrackView.cpp
@@ -24,6 +24,7 @@
  
 #include "PatternTrackView.h"
 
+#include "embed.h"
 #include "Engine.h"
 #include "GuiApplication.h"
 #include "PatternEditor.h"
diff --git a/src/gui/tracks/TrackContentWidget.cpp b/src/gui/tracks/TrackContentWidget.cpp
index 619eff8317b..f92b2602f1b 100644
--- a/src/gui/tracks/TrackContentWidget.cpp
+++ b/src/gui/tracks/TrackContentWidget.cpp
@@ -29,6 +29,7 @@
 #include <QMenu>
 #include <QPainter>
 
+#include "embed.h"
 #include "AutomationClip.h"
 #include "Clipboard.h"
 #include "DataFile.h"