diff --git a/externals/mrpeach/rc~/rc~.c b/externals/mrpeach/rc~/rc~.c
index 5cc750aca31a2290e3d94e068ed6367a8e534820..a7deefadc94f72a584857e418edb64b9b819b476 100644
--- a/externals/mrpeach/rc~/rc~.c
+++ b/externals/mrpeach/rc~/rc~.c
@@ -64,7 +64,7 @@ void rc_tilde_setup(void)
         CLASS_DEFAULT, 
         A_DEFFLOAT, 0);
 
-    class_addmethod(rc_tilde_class, (t_method)rc_tilde_dsp, gensym("dsp"), 0);
+    class_addmethod(rc_tilde_class, (t_method)rc_tilde_dsp, gensym("dsp"), A_CANT, 0);
     CLASS_MAINSIGNALIN(rc_tilde_class, t_rc_tilde, rc_f);
 }