diff --git a/source/SoundTouch/Makefile.am b/source/SoundTouch/Makefile.am
index 58c9e33..0453aa8 100644
--- a/source/SoundTouch/Makefile.am
+++ b/source/SoundTouch/Makefile.am
@@ -22,7 +22,8 @@ include $(top_srcdir)/config/am_include.mk
 # set to something if you want other stuff to be included in the distribution tarball
 EXTRA_DIST=SoundTouch.dsp SoundTouch.dsw SoundTouch.sln SoundTouch.vcproj
 
-noinst_HEADERS=AAFilter.h cpu_detect.h cpu_detect_x86.cpp FIRFilter.h RateTransposer.h TDStretch.h PeakFinder.h
+noinst_HEADERS=AAFilter.h cpu_detect.h cpu_detect_x86.cpp FIRFilter.h RateTransposer.h TDStretch.h PeakFinder.h \
+    InterpolateCubic.h InterpolateLinear.h InterpolateShannon.h
 
 lib_LTLIBRARIES=libSoundTouch.la
 #