diff --git a/gui_qt/bgslibrary_gui.pro b/gui_qt/bgslibrary_gui.pro
index 9486d316741421400361584565352f207b91d595..ddfd5a56cb62505cd5ed145b11954ab5c580f60d 100644
--- a/gui_qt/bgslibrary_gui.pro
+++ b/gui_qt/bgslibrary_gui.pro
@@ -129,7 +129,7 @@ SOURCES += bgslibrary_gui.cpp\
     ../package_bgs/VuMeter.cpp \
     ../package_bgs/WeightedMovingMean.cpp \
     ../package_bgs/WeightedMovingVariance.cpp \
-    ../package_bgs/_template_/amber/amber.c \
+    ../package_bgs/_template_/amber/amber.cpp \
     ../package_bgs/CodeBook.cpp
 
 HEADERS  += mainwindow.h \