diff --git a/render.py b/render.py
index e103788..3352ea3 100644
--- a/render.py
+++ b/render.py
@@ -216,7 +216,7 @@ def compose(clips, fragment, target=150, base=1024, voice_over=None, options=Non
     print("Voice Over:")
     if voice_over:
         vo_keys = list(sorted(voice_over))
-        while int(sub_offset * fps) < scene_duration:
+        while int(sub_offset * fps) < scene_duration and vo_keys:
             if sub_offset:
                 gap = (5 * fps + random_int(seq, 10 * fps)) / fps
             else: