diff --git a/gst/synaesthesia/synaescope.c b/gst/synaesthesia/synaescope.c
index b60d669aca..92abd399a3 100644
--- a/gst/synaesthesia/synaescope.c
+++ b/gst/synaesthesia/synaescope.c
@@ -337,7 +337,7 @@ synaesthesia_update (syn_instance * si, gint16 data[2][FFT_BUFFER_SIZE])
 }
 
 void
-synaesthesia_init ()
+synaesthesia_init (void)
 {
   static int inited = 0;
   int i;
diff --git a/gst/synaesthesia/synaescope.h b/gst/synaesthesia/synaescope.h
index ae1aba4d76..fe41a9a198 100644
--- a/gst/synaesthesia/synaescope.h
+++ b/gst/synaesthesia/synaescope.h
@@ -31,7 +31,7 @@
 
 typedef struct syn_instance syn_instance;
 
-void synaesthesia_init ();
+void synaesthesia_init (void);
 syn_instance *synaesthesia_new (guint resx, guint resy);
 void synaesthesia_close (syn_instance * si);