diff --git a/src/emucore/FrameBuffer.hxx b/src/emucore/FrameBuffer.hxx
index a86743911..b09d492f1 100644
--- a/src/emucore/FrameBuffer.hxx
+++ b/src/emucore/FrameBuffer.hxx
@@ -273,7 +273,7 @@ class FrameBuffer
     /**
       Toggles between adapt fullscreen refresh rate on and off.
     */
-    void FrameBuffer::toggleAdaptRefresh(bool toggle = true);
+    void toggleAdaptRefresh(bool toggle = true);
   #endif
 
     /**