Index: Modules/Pro/effects.c
--- Modules/Pro/effects.c.orig
+++ Modules/Pro/effects.c
@@ -207,8 +207,9 @@ LOCAL void do_vibrato(struct channel *ch)
       /* temporary update of only the step value,
        * note that we do not change the saved pitch.
        */
-   set_temp_pitch(ch, 
-		ch->pitch + sinusoid_value(&(ch->vib))/256);
+	if (ch->pitch)
+		set_temp_pitch(ch, 
+			ch->pitch + sinusoid_value(&(ch->vib))/256);
    }
 
 LOCAL void set_vibrato(struct channel *ch, struct event *e)
@@ -255,7 +256,7 @@ LOCAL void set_arpeggio(struct channel *ch, struct eve
 
       ch->arp[0] = note2pitch(ch->note, ch->finetune);
       note = ch->note + HI(e->parameters);
-         ch->arp[1] = note2pitch(ch->note, ch->finetune);
+         ch->arp[1] = note2pitch(note, ch->finetune);
 		if (!ch->arp[1])
          {
          status("Arpeggio note out of range");