diff --git a/src/devices/arranger.rs b/src/devices/arranger.rs
index 3c519a36..3a32e0c9 100644
--- a/src/devices/arranger.rs
+++ b/src/devices/arranger.rs
@@ -391,7 +391,7 @@ impl Arranger {
         self.selected.track().map(|t|self.tracks.get_mut(t)).flatten()
     }
     pub fn track_next (&mut self) {
-        self.selected.track_next(self.tracks.len())
+        self.selected.track_next(self.tracks.len() - 1)
     }
     pub fn track_prev (&mut self) {
         self.selected.track_prev()
@@ -421,7 +421,7 @@ impl Arranger {
         self.selected.scene().map(|s|self.scenes.get_mut(s)).flatten()
     }
     pub fn scene_next (&mut self) {
-        self.selected.scene_next(self.scenes.len())
+        self.selected.scene_next(self.scenes.len() - 1)
     }
     pub fn scene_prev (&mut self) {
         self.selected.scene_prev()