--- a/volume.c
+++ b/volume.c
@@ -74,6 +74,9 @@ static void remove_all_mixers() {
 static Slider *add_slider(Mixer *m, int dev) {
   Slider *result,*s;
   if (dev < 0 || dev >= mixer_get_nr_devices(m->mixer)) return NULL;
+  for (s = m->Sliderz ; s != NULL; s = s->next)
+    if (s->dev == dev)
+      return s;
   result = malloc(sizeof(Slider));
   result->mixer = m->mixer;
   result->parent = m;