diff --git a/cpdctrl/led_script.py b/cpdctrl/led_script.py
index ecb01df..ffce452 100644
--- a/cpdctrl/led_script.py
+++ b/cpdctrl/led_script.py
@@ -159,8 +159,10 @@ class LedScript:
     def _get_current_index(script, dt:float) -> int:
         if script.shape[0] == 1:
             return 0
+        if dt > script["dtsum"][-1]:  # if time is past the last index
+            return script["dtsum"].shape[0] - 1
         distance = script["dtsum"] - dt
-        idx = np.where(distance >= 0, distance, np.inf).argmin()
+        idx = int(np.where(distance >= 0, distance, np.inf).argmin())
         return idx
     
     def get_current_index(self, dt:float) -> int: