diff --git a/src/algorithms/signal_source/libs/CMakeLists.txt b/src/algorithms/signal_source/libs/CMakeLists.txt
index 3506dc4f7..19235ceac 100644
--- a/src/algorithms/signal_source/libs/CMakeLists.txt
+++ b/src/algorithms/signal_source/libs/CMakeLists.txt
@@ -9,12 +9,12 @@ set(OPT_SIGNAL_SOURCE_LIB_SOURCES "")
 set(OPT_SIGNAL_SOURCE_LIB_HEADERS "")
 if(ENABLE_FMCOMMS2 OR ENABLE_AD9361)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad9361_manager.cc)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad9361_manager.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} ad9361_manager.h)
 endif()
 
 if(ENABLE_MAX2771)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} fpga_spidev.cc)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} fpga_spidev.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} fpga_spidev.h)
 endif()
 
 if(ENABLE_FPGA)
@@ -36,10 +36,10 @@ endif()
 
 if(ENABLE_PLUTOSDR)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad936x_iio_samples.cc)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad936x_iio_samples.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} ad936x_iio_samples.h)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad936x_iio_custom.cc)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ad936x_iio_custom.h)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} pps_samplestamp.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} ad936x_iio_custom.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} pps_samplestamp.h)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ppstcprx.cc)
     set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} ppstcprx.h)
 endif()