diff --git a/src/algorithms/signal_source/libs/ad9361_manager.cc b/src/algorithms/signal_source/libs/ad9361_manager.cc
index 9be96a771..caab16ddc 100644
--- a/src/algorithms/signal_source/libs/ad9361_manager.cc
+++ b/src/algorithms/signal_source/libs/ad9361_manager.cc
@@ -189,7 +189,7 @@ bool config_ad9361_rx_local(uint64_t bandwidth_,
     bool quadrature_,
     bool rfdc_,
     bool bbdc_,
-    std::string filter_source_,
+    const std::string& filter_source_,
     std::string filter_filename_,
     float Fpass_,
     float Fstop_)
@@ -409,7 +409,7 @@ bool config_ad9361_rx_remote(const std::string &remote_host,
     bool quadrature_,
     bool rfdc_,
     bool bbdc_,
-    std::string filter_source_,
+    const std::string& filter_source_,
     std::string filter_filename_,
     float Fpass_,
     float Fstop_)
diff --git a/src/algorithms/signal_source/libs/ad9361_manager.h b/src/algorithms/signal_source/libs/ad9361_manager.h
index 0ca3d790a..14cf90b9e 100644
--- a/src/algorithms/signal_source/libs/ad9361_manager.h
+++ b/src/algorithms/signal_source/libs/ad9361_manager.h
@@ -93,7 +93,7 @@ bool config_ad9361_rx_local(uint64_t bandwidth_,
     bool quadrature_,
     bool rfdc_,
     bool bbdc_,
-    std::string filter_source_,
+    const std::string& filter_source_,
     std::string filter_filename_,
     float Fpass_,
     float Fstop_);