diff --git a/libs/ardour/audio_buffer.cc b/libs/ardour/audio_buffer.cc
index de2c1ddf00..6d8b2aa55f 100644
--- a/libs/ardour/audio_buffer.cc
+++ b/libs/ardour/audio_buffer.cc
@@ -43,7 +43,7 @@ AudioBuffer::AudioBuffer(size_t capacity)
 AudioBuffer::~AudioBuffer()
 {
 	if (_owns_data)
-		free(_data);
+		cache_aligned_free(_data);
 }
 
 void
@@ -60,7 +60,7 @@ AudioBuffer::resize (size_t size)
 		return;
 	}
 
-	free (_data);
+	cache_aligned_free (_data);
 
 	cache_aligned_malloc ((void**) &_data, sizeof (Sample) * size);
 
diff --git a/libs/ardour/midi_buffer.cc b/libs/ardour/midi_buffer.cc
index b1b09e4c98..50ff7b728f 100644
--- a/libs/ardour/midi_buffer.cc
+++ b/libs/ardour/midi_buffer.cc
@@ -44,7 +44,7 @@ MidiBuffer::MidiBuffer(size_t capacity)
 
 MidiBuffer::~MidiBuffer()
 {
-	free(_data);
+	cache_aligned_free(_data);
 }
 
 void
@@ -60,7 +60,7 @@ MidiBuffer::resize(size_t size)
 		return;
 	}
 
-	free (_data);
+	cache_aligned_free (_data);
 
 	cache_aligned_malloc ((void**) &_data, size);
 
diff --git a/libs/pbd/malign.cc b/libs/pbd/malign.cc
index a11a23f35f..a5f966c0c5 100644
--- a/libs/pbd/malign.cc
+++ b/libs/pbd/malign.cc
@@ -38,6 +38,15 @@ static const int CPU_CACHE_ALIGN = 16; /* arguably 32 on most arches, but it mat
 int cache_aligned_malloc (void** memptr, size_t size)
 {
 #ifndef HAVE_POSIX_MEMALIGN
+#ifdef PLATFORM_WINDOWS
+	if (((*memptr) = _aligned_malloc (size, CPU_CACHE_ALIGN)) == 0) {
+		fatal << string_compose (_("Memory allocation error: malloc (%1 * %2) failed (%3)"),
+					 CPU_CACHE_ALIGN, size, strerror (errno)) << endmsg;
+		return errno;
+	} else {
+		return 0;
+	}
+#else
 	if (((*memptr) = malloc (size)) == 0) {
 		fatal << string_compose (_("Memory allocation error: malloc (%1 * %2) failed (%3)"),
 					 CPU_CACHE_ALIGN, size, strerror (errno)) << endmsg;
@@ -45,6 +54,7 @@ int cache_aligned_malloc (void** memptr, size_t size)
 	} else {
 		return 0;
 	}
+#endif
 #else
         if (posix_memalign (memptr, CPU_CACHE_ALIGN, size)) {
 		fatal << string_compose (_("Memory allocation error: posix_memalign (%1 * %2) failed (%3)"),
@@ -54,3 +64,12 @@ int cache_aligned_malloc (void** memptr, size_t size)
 	return 0;
 #endif	
 }
+
+void cache_aligned_free (void* memptr)
+{
+#ifdef PLATFORM_WINDOWS
+	_aligned_free (memptr);
+#else
+	free (memptr);
+#endif
+}
\ No newline at end of file
diff --git a/libs/pbd/pbd/malign.h b/libs/pbd/pbd/malign.h
index 07f42f586f..ecee47c4e6 100644
--- a/libs/pbd/pbd/malign.h
+++ b/libs/pbd/pbd/malign.h
@@ -24,6 +24,7 @@
 
 #include "pbd/libpbd_visibility.h"
 
-LIBPBD_API int cache_aligned_malloc (void** memptr, size_t size);
+LIBPBD_API int  cache_aligned_malloc (void** memptr, size_t size);
+LIBPBD_API void cache_aligned_free (void* memptr);
 
 #endif /* __pbd_malign_h__ */