diff --git a/demo/main.fnl b/demo/main.fnl
index f1244a5..916b873 100644
--- a/demo/main.fnl
+++ b/demo/main.fnl
@@ -19,7 +19,7 @@
 (var transition-pending nil)
 
 (fn switch-demo [new-demo]
-  (when (not= active-demo new-demo)
+  (when (and (not= active-demo new-demo) (not transition))
     (set transition-pending new-demo)
     (set transition (pxl8.transition_create :pixelate 0.5))
     (pxl8.transition_set_color transition 0xFF000000)