diff --git a/aegisub/lavc_keyframes.cpp b/aegisub/lavc_keyframes.cpp
index bf9def605..2ea1f9614 100644
--- a/aegisub/lavc_keyframes.cpp
+++ b/aegisub/lavc_keyframes.cpp
@@ -43,7 +43,7 @@
 
 ///////////////
 // Constructor
-LAVCKeyFrames::LAVCKeyFrames(const Aegisub::String& filename) 
+LAVCKeyFrames::LAVCKeyFrames(const Aegisub::String filename) 
  : file(0), codecContext(0), codec(0), stream(0), frame(0), 
    streamN(-1) {
 	// Open LAVCFile
diff --git a/aegisub/lavc_keyframes.h b/aegisub/lavc_keyframes.h
index 843eb3d77..2844b7f25 100644
--- a/aegisub/lavc_keyframes.h
+++ b/aegisub/lavc_keyframes.h
@@ -48,7 +48,7 @@ class LAVCKeyFrames {
 
 		int streamN;					// Stream index
 	public:
-		LAVCKeyFrames(const Aegisub::String& filename);
+		LAVCKeyFrames(const Aegisub::String filename);
 		~LAVCKeyFrames();
 		wxArrayInt GetKeyFrames();
 };