diff --git a/externals/moonlib/panvol~.c b/externals/moonlib/panvol~.c
index 05709ff8b206f720097e0f53d1e0db48e64553e8..11bcc378b5042314d8674d5dedaf6871899b13d5 100644
--- a/externals/moonlib/panvol~.c
+++ b/externals/moonlib/panvol~.c
@@ -113,7 +113,7 @@ void panvol_tilde_setup(void)
 
     class_addmethod(pan_class, nullfn, gensym("signal"), 0);
 
-    class_addmethod(pan_class, (t_method)pan_dsp, gensym("dsp"), 0);
+    class_addmethod(pan_class, (t_method)pan_dsp, gensym("dsp"), A_CANT, 0);
     class_addmethod(pan_class, (t_method)pan_f, gensym("panf"), A_FLOAT, 0);
     class_addmethod(pan_class, (t_method)vol_f, gensym("volf"), A_FLOAT, 0);
 }
diff --git a/externals/moonlib/readsfv~.c b/externals/moonlib/readsfv~.c
index e3248acdfab23d3f7e94685fa3240768ad1e3d10..1c2cb5291c75d3d7a1f2da90a6b52078383c27f7 100644
--- a/externals/moonlib/readsfv~.c
+++ b/externals/moonlib/readsfv~.c
@@ -1693,7 +1693,7 @@ void readsfv_tilde_setup(void)
     class_addmethod(readsfv_class, (t_method)readsf_speed, gensym("speed"), A_FLOAT,0);
     class_addmethod(readsfv_class, (t_method)readsf_start, gensym("start"), 0);
     class_addmethod(readsfv_class, (t_method)readsf_stop, gensym("stop"), 0);
-    class_addmethod(readsfv_class, (t_method)readsf_dsp, gensym("dsp"), 0);
+    class_addmethod(readsfv_class, (t_method)readsf_dsp, gensym("dsp"), A_CANT, 0);
     class_addmethod(readsfv_class, (t_method)readsf_open, gensym("open"),
                     A_GIMME, 0);
     class_addmethod(readsfv_class, (t_method)readsf_print, gensym("print"), 0);
diff --git a/externals/moonlib/sfread2~.c b/externals/moonlib/sfread2~.c
index f32494df7872fb560aebe2de5b82329c2e8d5799..30e288031b4ea87bed1b5dcbe8091daca8ee6b94 100644
--- a/externals/moonlib/sfread2~.c
+++ b/externals/moonlib/sfread2~.c
@@ -415,7 +415,7 @@ void sfread2_tilde_setup(void)
                              (t_method)sfread_free,sizeof(t_sfread), 0,A_DEFFLOAT,A_DEFFLOAT,0);
 
     class_addmethod(sfread_class, nullfn, gensym("signal"), 0);
-    class_addmethod(sfread_class, (t_method) sfread_dsp, gensym("dsp"), 0);
+    class_addmethod(sfread_class, (t_method) sfread_dsp, gensym("dsp"), A_CANT, 0);
     class_addmethod(sfread_class, (t_method) sfread_open, gensym("open"), A_SYMBOL,A_NULL);
     class_addmethod(sfread_class, (t_method) sfread_size, gensym("size"), 0);
     class_addmethod(sfread_class, (t_method) sfread_state, gensym("state"), 0);
diff --git a/externals/moonlib/ssaw~.c b/externals/moonlib/ssaw~.c
index c57015e5b64b62f735e7db016c95dd75946f1636..fd6bb2486395f62119f266799110cacd8a790ef5 100644
--- a/externals/moonlib/ssaw~.c
+++ b/externals/moonlib/ssaw~.c
@@ -209,7 +209,7 @@ void ssaw_tilde_setup(void)
     ssaw_class = class_new(gensym("ssaw~"), (t_newmethod)ssaw_new, 0,
                            sizeof(t_ssaw), 0, A_DEFFLOAT, 0);
     CLASS_MAINSIGNALIN(ssaw_class, t_ssaw, x_f);
-    class_addmethod(ssaw_class, (t_method)ssaw_dsp, gensym("dsp"), 0);
+    class_addmethod(ssaw_class, (t_method)ssaw_dsp, gensym("dsp"), A_CANT, 0);
     class_addmethod(ssaw_class, (t_method)ssaw_ft1,
                     gensym("ft1"), A_FLOAT, 0);
     ssaw_initarray();