diff --git a/audiodevice.cpp b/audiodevice.cpp
index 88443b2..d71b850 100644
--- a/audiodevice.cpp
+++ b/audiodevice.cpp
@@ -4,7 +4,6 @@
 #include <QIODevice>
 #include <QAudioInput>
 
-namespace {
 //! private helper to allow QAudioInput to write to a io device
 class AudioDeviceHelper : public QIODevice
 {
@@ -18,14 +17,13 @@ private:
     AudioDevice &m_audioDevice;
 };
 
-class AudioDevicePrivate {
+class AudioDevice::AudioDevicePrivate {
 public:
     AudioDevicePrivate(AudioDevice &audioDevice, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format);
 
     AudioDeviceHelper helper;
     QAudioInput input;
 };
-}
 
 AudioDevice::AudioDevice(QObject *parent) :
     BaseDevice{parent}
@@ -58,9 +56,6 @@ void AudioDevice::stop()
     m_private = nullptr;
 }
 
-
-
-namespace {
 AudioDeviceHelper::AudioDeviceHelper(AudioDevice &audioDevice, QObject *parent) :
     QIODevice{parent}, m_audioDevice(audioDevice)
 {
@@ -84,8 +79,7 @@ qint64 AudioDeviceHelper::writeData(const char *data, qint64 len)
     return len;
 }
 
-AudioDevicePrivate::AudioDevicePrivate(AudioDevice &audioDevice, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format) :
+AudioDevice::AudioDevicePrivate::AudioDevicePrivate(AudioDevice &audioDevice, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format) :
     helper{audioDevice}, input{audioDeviceInfo, format}
 {
 }
-}
diff --git a/audiodevice.h b/audiodevice.h
index bcd319b..656cb0b 100644
--- a/audiodevice.h
+++ b/audiodevice.h
@@ -9,7 +9,6 @@
 #include <memory>
 
 // forward declares
-namespace { class AudioDevicePrivate; }
 class QAudioInput;
 
 class AudioDevice : public BaseDevice
@@ -31,6 +30,7 @@ public:
     void setDevice(const QAudioDeviceInfo &device) { Q_ASSERT(!running()); m_device = device; }
 
 private:
+    class AudioDevicePrivate;
     std::unique_ptr<AudioDevicePrivate> m_private;
 
     int m_samplerate;
diff --git a/basetonegenerator.cpp b/basetonegenerator.cpp
index 94e65be..163f488 100644
--- a/basetonegenerator.cpp
+++ b/basetonegenerator.cpp
@@ -3,8 +3,6 @@
 // Qt includes
 #include <QAudioOutput>
 
-namespace
-{
 //! private helper to allow QAudioOutput to read from a io device
 class BaseToneGeneratorHelper : public QIODevice
 {
@@ -18,7 +16,7 @@ private:
     BaseToneGenerator &m_generator;
 };
 
-class BaseToneGeneratorPrivate
+class BaseToneGenerator::BaseToneGeneratorPrivate
 {
 public:
     BaseToneGeneratorPrivate(BaseToneGenerator &generator, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format);
@@ -28,8 +26,6 @@ public:
     QAudioOutput output;
 };
 
-}
-
 BaseToneGenerator::BaseToneGenerator() = default;
 
 BaseToneGenerator::~BaseToneGenerator() = default;
@@ -58,7 +54,6 @@ void BaseToneGenerator::stop()
     m_private = nullptr;
 }
 
-namespace {
 BaseToneGeneratorHelper::BaseToneGeneratorHelper(BaseToneGenerator &generator, QObject *parent) :
     QIODevice{parent}, m_generator{generator}
 {
@@ -80,8 +75,7 @@ qint64 BaseToneGeneratorHelper::writeData(const char *data, qint64 len)
     qFatal("writing is not allowed!");
 }
 
-BaseToneGeneratorPrivate::BaseToneGeneratorPrivate(BaseToneGenerator &generator, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format) :
+BaseToneGenerator::BaseToneGeneratorPrivate::BaseToneGeneratorPrivate(BaseToneGenerator &generator, const QAudioDeviceInfo &audioDeviceInfo, const QAudioFormat &format) :
     helper{generator}, output{audioDeviceInfo, format}
 {
 }
-}
diff --git a/basetonegenerator.h b/basetonegenerator.h
index 1c8b25f..b3d2397 100644
--- a/basetonegenerator.h
+++ b/basetonegenerator.h
@@ -9,9 +9,6 @@
 // local includes
 #include "oscicommon.h"
 
-// forward declares
-namespace { class BaseToneGeneratorPrivate; }
-
 class BaseToneGenerator
 {
 public:
@@ -31,6 +28,7 @@ public:
     virtual std::size_t fill(SamplePair *begin, SamplePair *end) = 0;
 
 private:
+    class BaseToneGeneratorPrivate;
     std::unique_ptr<BaseToneGeneratorPrivate> m_private;
 
     int m_samplerate;