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--- a/Makefile.am
+++ b/Makefile.am
@@ -32,6 +32,8 @@
     libupnpp/control/ohproduct.hxx \
     libupnpp/control/ohtime.cxx \
     libupnpp/control/ohtime.hxx \
+    libupnpp/control/ohvolume.cxx \
+    libupnpp/control/ohvolume.hxx \
     libupnpp/control/renderingcontrol.cxx \
     libupnpp/control/renderingcontrol.hxx \
     libupnpp/control/service.cxx \
@@ -74,6 +76,7 @@
     libupnpp/control/ohplaylist.hxx \
     libupnpp/control/ohproduct.hxx \
     libupnpp/control/ohtime.hxx \
+    libupnpp/control/ohvolume.hxx \
     libupnpp/control/renderingcontrol.hxx \
     libupnpp/control/service.hxx \
     libupnpp/device/device.hxx \