diff --git a/include/MidiPort.h b/include/MidiPort.h
index c8a3c6e44..07c61d788 100644
--- a/include/MidiPort.h
+++ b/include/MidiPort.h
@@ -124,6 +124,8 @@ public:
 		return m_writablePorts;
 	}
 
+	void invalidateCilent();
+
 	MidiPortMenu* m_readablePortsMenu;
 	MidiPortMenu* m_writablePortsMenu;
 
diff --git a/include/MixerWorkerThread.h b/include/MixerWorkerThread.h
index 9bf2be077..7c3792392 100644
--- a/include/MixerWorkerThread.h
+++ b/include/MixerWorkerThread.h
@@ -47,10 +47,10 @@ public:
 			Dynamic	// jobs can be added while processing queue
 		} ;
 
-#define JOB_QUEUE_SIZE 1024
+#define JOB_QUEUE_SIZE 8192
 		JobQueue() :
 			m_items(),
-			m_queueSize( 0 ),
+			m_writeIndex( 0 ),
 			m_itemsDone( 0 ),
 			m_opMode( Static )
 		{
@@ -66,7 +66,7 @@ public:
 
 	private:
 		std::atomic<ThreadableJob*> m_items[JOB_QUEUE_SIZE];
-		std::atomic_int m_queueSize;
+		std::atomic_int m_writeIndex;
 		std::atomic_int m_itemsDone;
 		OperationMode m_opMode;
 
diff --git a/plugins/Flanger/FlangerControls.cpp b/plugins/Flanger/FlangerControls.cpp
index 4ba91dba3..fa3640db4 100644
--- a/plugins/Flanger/FlangerControls.cpp
+++ b/plugins/Flanger/FlangerControls.cpp
@@ -43,6 +43,7 @@ FlangerControls::FlangerControls( FlangerEffect *effect ) :
 
 {
 	connect( Engine::mixer(), SIGNAL( sampleRateChanged() ), this, SLOT( changedSampleRate() ) );
+	connect( Engine::getSong(), SIGNAL( playbackStateChanged() ), this, SLOT( changedPlaybackState() ) );
 }
 
 
@@ -81,3 +82,9 @@ void FlangerControls::changedSampleRate()
 }
 
 
+
+
+void FlangerControls::changedPlaybackState()
+{
+	m_effect->restartLFO();
+}
diff --git a/plugins/Flanger/FlangerControls.h b/plugins/Flanger/FlangerControls.h
index bbd8444fa..d51141ed0 100644
--- a/plugins/Flanger/FlangerControls.h
+++ b/plugins/Flanger/FlangerControls.h
@@ -57,6 +57,7 @@ public:
 
 private slots:
 	void changedSampleRate();
+	void changedPlaybackState();
 
 private:
 	FlangerEffect* m_effect;
diff --git a/plugins/Flanger/FlangerEffect.cpp b/plugins/Flanger/FlangerEffect.cpp
index 2f5d96ef5..1404c06b0 100644
--- a/plugins/Flanger/FlangerEffect.cpp
+++ b/plugins/Flanger/FlangerEffect.cpp
@@ -68,7 +68,7 @@ FlangerEffect::~FlangerEffect()
 	{
 		delete m_rDelay;
 	}
-	if(m_lfo )
+	if( m_lfo )
 	{
 		delete m_lfo;
 	}
@@ -139,6 +139,15 @@ void FlangerEffect::changeSampleRate()
 
 
 
+
+void FlangerEffect::restartLFO()
+{
+	m_lfo->restart();
+}
+
+
+
+
 extern "C"
 {
 
diff --git a/plugins/Flanger/FlangerEffect.h b/plugins/Flanger/FlangerEffect.h
index ad1052b5a..a70e87827 100644
--- a/plugins/Flanger/FlangerEffect.h
+++ b/plugins/Flanger/FlangerEffect.h
@@ -44,6 +44,7 @@ public:
 		return &m_flangerControls;
 	}
 	void changeSampleRate();
+	void restartLFO();
 
 private:
 	FlangerControls m_flangerControls;
diff --git a/plugins/Flanger/QuadratureLfo.h b/plugins/Flanger/QuadratureLfo.h
index 90f7f77dc..e7e27d14a 100644
--- a/plugins/Flanger/QuadratureLfo.h
+++ b/plugins/Flanger/QuadratureLfo.h
@@ -53,6 +53,14 @@ public:
 
 
 
+	inline void restart()
+	{
+		m_phase = 0;
+	}
+
+
+
+
 	inline void setSampleRate ( int samplerate )
 	{
 		m_samplerate = samplerate;
diff --git a/src/core/ConfigManager.cpp b/src/core/ConfigManager.cpp
index 177a90437..f52e10ac7 100644
--- a/src/core/ConfigManager.cpp
+++ b/src/core/ConfigManager.cpp
@@ -292,9 +292,7 @@ void ConfigManager::setDefaultSoundfont( const QString & _sf )
 
 void ConfigManager::setBackgroundArtwork( const QString & _ba )
 {
-#ifdef LMMS_HAVE_FLUIDSYNTH
 	m_backgroundArtwork = _ba;
-#endif
 }
 
 void ConfigManager::setGIGDir(const QString &gd)
diff --git a/src/core/InstrumentFunctions.cpp b/src/core/InstrumentFunctions.cpp
index 5a87b54dd..a2aecb9c9 100644
--- a/src/core/InstrumentFunctions.cpp
+++ b/src/core/InstrumentFunctions.cpp
@@ -344,7 +344,7 @@ void InstrumentFunctionArpeggio::processNote( NotePlayHandle * _n )
 	if( _n->origin() == NotePlayHandle::OriginArpeggio ||
 		_n->origin() == NotePlayHandle::OriginNoteStacking ||
 		!m_arpEnabledModel.value() ||
-		( _n->isReleased() && _n->releaseFramesDone() >= _n->actualReleaseFramesToDo() ) )
+		_n->isReleased() )
 	{
 		return;
 	}
@@ -412,7 +412,6 @@ void InstrumentFunctionArpeggio::processNote( NotePlayHandle * _n )
 		// Skip notes randomly
 		if( m_arpSkipModel.value() )
 		{
-
 			if( 100 * ( (float) rand() / (float)( RAND_MAX + 1.0f ) ) < m_arpSkipModel.value() )
 			{
 				// Set master note to prevent the note to extend over skipped notes
@@ -501,12 +500,6 @@ void InstrumentFunctionArpeggio::processNote( NotePlayHandle * _n )
 			continue;
 		}
 
-		float vol_level = 1.0f;
-		if( _n->isReleased() )
-		{
-			vol_level = _n->volumeLevel( cur_frame + gated_frames );
-		}
-
 		// create new arp-note
 
 		// create sub-note-play-handle, only ptr to note is different
@@ -515,7 +508,7 @@ void InstrumentFunctionArpeggio::processNote( NotePlayHandle * _n )
 				NotePlayHandleManager::acquire( _n->instrumentTrack(),
 							frames_processed,
 							gated_frames,
-							Note( MidiTime( 0 ), MidiTime( 0 ), sub_note_key, (volume_t) qRound( _n->getVolume() * vol_level ),
+							Note( MidiTime( 0 ), MidiTime( 0 ), sub_note_key, _n->getVolume(),
 									_n->getPanning(), _n->detuning() ),
 							_n, -1, NotePlayHandle::OriginArpeggio )
 				);
diff --git a/src/core/MixerWorkerThread.cpp b/src/core/MixerWorkerThread.cpp
index d7e252528..9632d22c7 100644
--- a/src/core/MixerWorkerThread.cpp
+++ b/src/core/MixerWorkerThread.cpp
@@ -25,6 +25,7 @@
 #include "MixerWorkerThread.h"
 
 #include <xmmintrin.h>
+#include <QDebug>
 #include <QMutex>
 #include <QWaitCondition>
 
@@ -39,7 +40,7 @@ QList<MixerWorkerThread *> MixerWorkerThread::workerThreads;
 // implementation of internal JobQueue
 void MixerWorkerThread::JobQueue::reset( OperationMode _opMode )
 {
-	m_queueSize = 0;
+	m_writeIndex = 0;
 	m_itemsDone = 0;
 	m_opMode = _opMode;
 }
@@ -54,7 +55,13 @@ void MixerWorkerThread::JobQueue::addJob( ThreadableJob * _job )
 		// update job state
 		_job->queue();
 		// actually queue the job via atomic operations
-		m_items[m_queueSize++] = _job;
+		auto index = m_writeIndex++;
+		if (index < JOB_QUEUE_SIZE) {
+			m_items[index] = _job;
+		} else {
+			qWarning() << "Job queue is full!";
+			++m_itemsDone;
+		}
 	}
 }
 
@@ -63,10 +70,10 @@ void MixerWorkerThread::JobQueue::addJob( ThreadableJob * _job )
 void MixerWorkerThread::JobQueue::run()
 {
 	bool processedJob = true;
-	while (processedJob && m_itemsDone < m_queueSize)
+	while (processedJob && m_itemsDone < m_writeIndex)
 	{
 		processedJob = false;
-		for( int i = 0; i < m_queueSize; ++i )
+		for( int i = 0; i < m_writeIndex && i < JOB_QUEUE_SIZE; ++i )
 		{
 			ThreadableJob * job = m_items[i].exchange(nullptr);
 			if( job )
@@ -86,7 +93,7 @@ void MixerWorkerThread::JobQueue::run()
 
 void MixerWorkerThread::JobQueue::wait()
 {
-	while (m_itemsDone < m_queueSize)
+	while (m_itemsDone < m_writeIndex)
 	{
 #if defined(LMMS_HOST_X86) || defined(LMMS_HOST_X86_64)
 		_mm_pause();
diff --git a/src/core/Track.cpp b/src/core/Track.cpp
index c8f68d459..15de5a983 100644
--- a/src/core/Track.cpp
+++ b/src/core/Track.cpp
@@ -143,7 +143,9 @@ void TrackContentObject::movePosition( const MidiTime & pos )
 {
 	if( m_startPosition != pos )
 	{
+		Engine::mixer()->requestChangeInModel();
 		m_startPosition = pos;
+		Engine::mixer()->doneChangeInModel();
 		Engine::getSong()->updateLength();
 		emit positionChanged();
 	}
diff --git a/src/core/midi/MidiClient.cpp b/src/core/midi/MidiClient.cpp
index 8ba70bcb7..b88c64db1 100644
--- a/src/core/midi/MidiClient.cpp
+++ b/src/core/midi/MidiClient.cpp
@@ -38,6 +38,10 @@ MidiClient::MidiClient()
 MidiClient::~MidiClient()
 {
 	//TODO: noteOffAll(); / clear all ports
+	for (MidiPort* port : m_midiPorts)
+	{
+		port->invalidateCilent();
+	}
 }
 
 
diff --git a/src/core/midi/MidiPort.cpp b/src/core/midi/MidiPort.cpp
index 43019876e..9e3cdb13d 100644
--- a/src/core/midi/MidiPort.cpp
+++ b/src/core/midi/MidiPort.cpp
@@ -27,9 +27,12 @@
 
 #include "MidiPort.h"
 #include "MidiClient.h"
+#include "MidiDummy.h"
 #include "Note.h"
 #include "Song.h"
 
+static MidiDummy s_dummyClient;
+
 
 
 MidiPort::MidiPort( const QString& name,
@@ -410,4 +413,7 @@ void MidiPort::updateOutputProgram()
 
 
 
-
+void MidiPort::invalidateCilent()
+{
+	m_midiClient = &s_dummyClient;
+}
diff --git a/src/gui/Forms/EffectSelectDialog.ui b/src/gui/Forms/EffectSelectDialog.ui
index a9c6de019..f8e773486 100644
--- a/src/gui/Forms/EffectSelectDialog.ui
+++ b/src/gui/Forms/EffectSelectDialog.ui
@@ -102,6 +102,7 @@
  <customwidgets>
   <customwidget>
    <class>RowTableView</class>
+   <extends>QTableView</extends>
    <header>RowTableView.h</header>
   </customwidget>
  </customwidgets>
diff --git a/src/gui/SetupDialog.cpp b/src/gui/SetupDialog.cpp
index f88e1dcf6..5063761e2 100644
--- a/src/gui/SetupDialog.cpp
+++ b/src/gui/SetupDialog.cpp
@@ -1525,9 +1525,7 @@ void SetupDialog::setDefaultSoundfont( const QString & _sf )
 
 void SetupDialog::setBackgroundArtwork( const QString & _ba )
 {
-#ifdef LMMS_HAVE_FLUIDSYNTH
 	m_backgroundArtwork = _ba;
-#endif
 }