diff --git a/Audio/soundin.cpp b/Audio/soundin.cpp
index 19c41f61b..ad9e43444 100644
--- a/Audio/soundin.cpp
+++ b/Audio/soundin.cpp
@@ -82,7 +82,11 @@ void SoundInput::start(QAudioDeviceInfo const& device, int framesPerBuffer, Audi
   //qDebug () << "SoundIn default buffer size (bytes):" << m_stream->bufferSize () << "period size:" << m_stream->periodSize ();
   // the Windows MME version of QAudioInput uses 1/5 of the buffer
   // size for period size other platforms seem to optimize themselves
+#if defined (Q_OS_WIN)
   m_stream->setBufferSize (m_stream->format ().bytesForFrames (framesPerBuffer * 5));
+#else
+  Q_UNUSED (framesPerBuffer);
+#endif
   if (sink->initialize (QIODevice::WriteOnly, channel))
     {
       m_stream->start (sink);
diff --git a/Audio/soundout.cpp b/Audio/soundout.cpp
index 71625a3f6..cda5fa333 100644
--- a/Audio/soundout.cpp
+++ b/Audio/soundout.cpp
@@ -85,7 +85,9 @@ void SoundOutput::restart (QIODevice * source)
   //qDebug () << "SoundOut default buffer size (bytes):" << m_stream->bufferSize () << "period size:" << m_stream->periodSize ();
   if (m_framesBuffered)
     {
+#if defined (Q_OS_WIN)
       m_stream->setBufferSize (m_stream->format().bytesForFrames (m_framesBuffered));
+#endif
     }
   m_stream->setCategory ("production");
   m_stream->start (source);