diff --git a/render.py b/render.py
index d4b3a43..285cc36 100644
--- a/render.py
+++ b/render.py
@@ -268,6 +268,8 @@ def compose(clips, fragment, target=150, base=1024, voice_over=None, options=Non
             #    a, b = '5', '-1'
             if vo_b:
                 a, b = '2', '-4'
+                vo_b_a = '1'
+                vo_b_b = '5'
             voc['filter'] = {'volume': a}
             scene['audio-center']['A1'].append(voc)
             vo_low = vo.copy()
@@ -280,10 +282,10 @@ def compose(clips, fragment, target=150, base=1024, voice_over=None, options=Non
                 subs.append(sub)
             if vo_b:
                 vo_b = vo_b.copy()
-                vo_b['filter'] = {'volume': a}
+                vo_b['filter'] = {'volume': vo_b_a}
                 scene['audio-center']['A2'].append(vo_b)
                 vo_b = vo_b.copy()
-                vo_b['filter'] = {'volume': b}
+                vo_b['filter'] = {'volume': vo_b_b}
                 scene['audio-rear']['A2'].append(vo_b)
             else:
                 for tl, track in (