diff --git a/libs/ardour/ardour/mp3fileimportable.h b/libs/ardour/ardour/mp3fileimportable.h
index 61d40cd35a..1da65d0925 100644
--- a/libs/ardour/ardour/mp3fileimportable.h
+++ b/libs/ardour/ardour/mp3fileimportable.h
@@ -20,7 +20,6 @@
 #ifndef _ardour_mp3file_importable_source_h_
 #define _ardour_mp3file_importable_source_h_
 
-#include <boost/shared_ptr.hpp>
 #include "ardour/libardour_visibility.h"
 #include "ardour/types.h"
 #include "ardour/importable_source.h"
diff --git a/libs/ardour/mp3fileimportable.cc b/libs/ardour/mp3fileimportable.cc
index 9d79b1be8a..d2ab4ad5bb 100644
--- a/libs/ardour/mp3fileimportable.cc
+++ b/libs/ardour/mp3fileimportable.cc
@@ -33,9 +33,10 @@
 #include "pbd/error.h"
 #include "ardour/mp3fileimportable.h"
 
-using namespace ARDOUR;
 using namespace std;
 
+namespace ARDOUR {
+
 Mp3FileImportableSource::Mp3FileImportableSource (const string& path)
 	: _fd (-1)
 	, _map_addr (0)
@@ -235,3 +236,5 @@ Mp3FileImportableSource::read_unlocked (Sample* dst, samplepos_t start, samplecn
 	}
 	return dst_off;
 }
+
+}
diff --git a/msvc_extra_headers/immintrin.h.input b/msvc_extra_headers/immintrin.h.input
new file mode 100644
index 0000000000..0f8743b164
--- /dev/null
+++ b/msvc_extra_headers/immintrin.h.input
@@ -0,0 +1,4 @@
+/*
+** Emtpy file to prevent Win32 compiler from complaining that the
+** file doesn't exist.
+*/