diff --git a/src/core/source/AudioSourceClipSeries.cpp b/src/core/source/AudioSourceClipSeries.cpp
index ecf2396..69f7184 100644
--- a/src/core/source/AudioSourceClipSeries.cpp
+++ b/src/core/source/AudioSourceClipSeries.cpp
@@ -94,6 +94,7 @@ namespace talcs {
     bool AudioSourceClipSeries::open(qint64 bufferSize, double sampleRate) {
         Q_D(AudioSourceClipSeries);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (d->openAllClips(bufferSize, sampleRate))
             return AudioSource::open(bufferSize, sampleRate);
         return false;
diff --git a/src/core/source/BufferingAudioSource.cpp b/src/core/source/BufferingAudioSource.cpp
index b91d547..944c743 100644
--- a/src/core/source/BufferingAudioSource.cpp
+++ b/src/core/source/BufferingAudioSource.cpp
@@ -132,6 +132,7 @@ namespace talcs {
     bool BufferingAudioSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(BufferingAudioSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         flush();
         if (!d->src->open(bufferSize, sampleRate))
             return false;
diff --git a/src/core/source/FutureAudioSource.cpp b/src/core/source/FutureAudioSource.cpp
index d551252..5799b87 100644
--- a/src/core/source/FutureAudioSource.cpp
+++ b/src/core/source/FutureAudioSource.cpp
@@ -174,6 +174,7 @@ namespace talcs {
     bool FutureAudioSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(FutureAudioSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         switch (status()) {
             case Running:
             case Paused:
diff --git a/src/core/source/FutureAudioSourceClipSeries.cpp b/src/core/source/FutureAudioSourceClipSeries.cpp
index 396628e..38070f0 100644
--- a/src/core/source/FutureAudioSourceClipSeries.cpp
+++ b/src/core/source/FutureAudioSourceClipSeries.cpp
@@ -164,6 +164,7 @@ namespace talcs {
     bool FutureAudioSourceClipSeries::open(qint64 bufferSize, double sampleRate) {
         Q_D(FutureAudioSourceClipSeries);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (d->openAllClips(bufferSize, sampleRate))
             return AudioSource::open(bufferSize, sampleRate);
         return false;
diff --git a/src/core/source/MetronomeAudioSource.cpp b/src/core/source/MetronomeAudioSource.cpp
index 60368a5..47b475f 100644
--- a/src/core/source/MetronomeAudioSource.cpp
+++ b/src/core/source/MetronomeAudioSource.cpp
@@ -79,6 +79,7 @@ namespace talcs {
     bool MetronomeAudioSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(MetronomeAudioSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (d->majorBeatSource)
             if (!d->majorBeatSource->open(bufferSize, sampleRate))
                 return false;
diff --git a/src/core/source/MixerAudioSource.cpp b/src/core/source/MixerAudioSource.cpp
index 6943709..48f61e2 100644
--- a/src/core/source/MixerAudioSource.cpp
+++ b/src/core/source/MixerAudioSource.cpp
@@ -60,6 +60,7 @@ namespace talcs {
     bool MixerAudioSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(MixerAudioSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (d->start(bufferSize, sampleRate)) {
             return AudioSource::open(bufferSize, sampleRate);
         } else {
diff --git a/src/core/source/NoteSynthesizer.cpp b/src/core/source/NoteSynthesizer.cpp
index f14672f..12e46d2 100644
--- a/src/core/source/NoteSynthesizer.cpp
+++ b/src/core/source/NoteSynthesizer.cpp
@@ -339,6 +339,7 @@ namespace talcs {
 
     bool NoteSynthesizer::open(qint64 bufferSize, double sampleRate) {
         Q_D(NoteSynthesizer);
+        AudioSource::close();
         flush(true);
         return AudioSource::open(bufferSize, sampleRate);
     }
diff --git a/src/core/source/PositionableMixerAudioSource.cpp b/src/core/source/PositionableMixerAudioSource.cpp
index b261023..7c49cbc 100644
--- a/src/core/source/PositionableMixerAudioSource.cpp
+++ b/src/core/source/PositionableMixerAudioSource.cpp
@@ -61,6 +61,7 @@ namespace talcs {
         Q_D(PositionableMixerAudioSource);
         QMutexLocker locker(&d->mutex);
         d->stop();
+        AudioSource::close();
         if (d->start(bufferSize, sampleRate)) {
             d->setNextReadPositionToAll(d->position);
             return PositionableAudioSource::open(bufferSize, sampleRate);
diff --git a/src/core/source/SineWaveAudioSource.cpp b/src/core/source/SineWaveAudioSource.cpp
index 1dc9e0c..0e59ce0 100644
--- a/src/core/source/SineWaveAudioSource.cpp
+++ b/src/core/source/SineWaveAudioSource.cpp
@@ -49,10 +49,6 @@ namespace talcs {
         setFrequency(frequencyIntegration);
     }
 
-    bool SineWaveAudioSource::open(qint64 bufferSize, double sampleRate) {
-        return AudioSource::open(bufferSize, sampleRate);
-    }
-
     qint64 SineWaveAudioSource::processReading(const AudioSourceReadData &readData) {
         Q_D(SineWaveAudioSource);
         QMutexLocker locker(&d->mutex);
diff --git a/src/core/source/SineWaveAudioSource.h b/src/core/source/SineWaveAudioSource.h
index 4483c13..080d48c 100644
--- a/src/core/source/SineWaveAudioSource.h
+++ b/src/core/source/SineWaveAudioSource.h
@@ -35,7 +35,6 @@ namespace talcs {
         explicit SineWaveAudioSource(const std::function<double(qint64)> &frequencyIntegration);
         ~SineWaveAudioSource() override = default;
 
-        bool open(qint64 bufferSize, double sampleRate) override;
         qint64 length() const override;
 
         void setFrequency(double frequency);
diff --git a/src/core/source/TransportAudioSource.cpp b/src/core/source/TransportAudioSource.cpp
index 42464d4..514565d 100644
--- a/src/core/source/TransportAudioSource.cpp
+++ b/src/core/source/TransportAudioSource.cpp
@@ -122,6 +122,7 @@ namespace talcs {
     bool TransportAudioSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(TransportAudioSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         d->playbackStatus = Paused;
         if (d->src && !d->src->open(bufferSize, sampleRate)) {
             return false;
diff --git a/src/format/source/AudioFormatInputSource.cpp b/src/format/source/AudioFormatInputSource.cpp
index d133ad8..e7b90c9 100644
--- a/src/format/source/AudioFormatInputSource.cpp
+++ b/src/format/source/AudioFormatInputSource.cpp
@@ -117,6 +117,7 @@ namespace talcs {
     bool AudioFormatInputSource::open(qint64 bufferSize, double sampleRate) {
         Q_D(AudioFormatInputSource);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (!d->io)
             return false;
         if (d->io->open(AbstractAudioFormatIO::Read)) {
diff --git a/src/midi/integrator/AbstractMidiMessageIntegrator.cpp b/src/midi/integrator/AbstractMidiMessageIntegrator.cpp
index a1c39b3..db75e86 100644
--- a/src/midi/integrator/AbstractMidiMessageIntegrator.cpp
+++ b/src/midi/integrator/AbstractMidiMessageIntegrator.cpp
@@ -35,6 +35,7 @@ namespace talcs {
     bool AbstractMidiMessageIntegrator::open(qint64 bufferSize, double sampleRate) {
         Q_D(AbstractMidiMessageIntegrator);
         QMutexLocker locker(&d->mutex);
+        AudioSource::close();
         if (d->stream && !d->stream->open(bufferSize, sampleRate))
             return false;
         return AudioSource::open(bufferSize, sampleRate);
diff --git a/src/midi/integrator/AudioMidiStream.cpp b/src/midi/integrator/AudioMidiStream.cpp
index 4b141fe..a197006 100644
--- a/src/midi/integrator/AudioMidiStream.cpp
+++ b/src/midi/integrator/AudioMidiStream.cpp
@@ -32,6 +32,7 @@ namespace talcs {
     bool AudioMidiStream::open(qint64 bufferSize, double sampleRate) {
         Q_D(AudioMidiStream);
         QMutexLocker locker(&d->filterMutex);
+        AudioStreamBase::close();
         if (d->filter.loadRelaxed() && !d->filter.loadRelaxed()->open(bufferSize, sampleRate)) {
             return false;
         }