diff --git a/libs/ardour/ardour/mixer_snapshot_manager.h b/libs/ardour/ardour/mixer_snapshot_manager.h
index 8d91c094d2..fff31da4bc 100644
--- a/libs/ardour/ardour/mixer_snapshot_manager.h
+++ b/libs/ardour/ardour/mixer_snapshot_manager.h
@@ -39,8 +39,8 @@ public:
     MixerSnapshotManager (ARDOUR::Session*);
     ~MixerSnapshotManager() {}
 
-    void create_snapshot(std::string const& label, RouteList& rl, bool global);
-    void create_snapshot(std::string const& label, std::string const& from_path, bool global);
+    void create_snapshot(const std::string& label, RouteList& rl, bool global);
+    void create_snapshot(const std::string& label, const std::string& from_path, bool global);
 
     bool rename_snapshot(MixerSnapshot*, const std::string&);
     bool remove_snapshot(MixerSnapshot*);
diff --git a/libs/ardour/mixer_snapshot_manager.cc b/libs/ardour/mixer_snapshot_manager.cc
index 6f173440d7..aab9719650 100644
--- a/libs/ardour/mixer_snapshot_manager.cc
+++ b/libs/ardour/mixer_snapshot_manager.cc
@@ -197,7 +197,7 @@ MixerSnapshot* MixerSnapshotManager::get_snapshot_by_name(const string& name, bo
     }
 }
 
-void MixerSnapshotManager::create_snapshot(std::string const& label, RouteList& rl, bool global)
+void MixerSnapshotManager::create_snapshot(const string& label, RouteList& rl, bool global)
 {
     ensure_snapshot_dir(global);
     const string path = global ? _global_path : _local_path;
@@ -236,7 +236,7 @@ void MixerSnapshotManager::create_snapshot(std::string const& label, RouteList&
     snapshots_list.insert(snapshot);
 }
 
-void MixerSnapshotManager::create_snapshot(std::string const& label, std::string const& from_path, bool global)
+void MixerSnapshotManager::create_snapshot(const string& label, const string& from_path, bool global)
 {
     ensure_snapshot_dir(global);
     const string path = global ? _global_path : _local_path;