diff --git a/pizzactrl/hal_serial.py b/pizzactrl/hal_serial.py
index 410f64e..0affc18 100644
--- a/pizzactrl/hal_serial.py
+++ b/pizzactrl/hal_serial.py
@@ -4,7 +4,7 @@ import threading
 from time import sleep
 from enum import Enum
 
-from typing import Any, List
+from typing import Any, List, Iterable
 from scipy.io.wavfile import write as writewav
 
 import sounddevice as sd
@@ -181,8 +181,7 @@ def turn_off(hal: PizzaHAL, **kwargs):
     """
     Turn off the lights.
     """
-    hal.send_cmd(SerialCommands.BACKLIGHT, 0)
-    hal.send_cmd(SerialCommands.FRONTLIGHT, 0)
+    light(hal, [SerialCommands.BACKLIGHT, SerialCommands.FRONTLIGHT], 0, 0, 0, 0, 0)
 
 
 def wait_for_input(hal: PizzaHAL,
@@ -243,12 +242,12 @@ def wait_for_input(hal: PizzaHAL,
 
 
 def light(hal: PizzaHAL,
+          light: Iterable,
           r: float, 
           g: float, 
           b: float, 
           w: float, 
-          fade: float = 0.0, 
-          backlight: bool = False,
+          fade: float = 0.0,
           **kwargs):
     """
     Turn on the light to illuminate the upper scroll
@@ -261,12 +260,14 @@ def light(hal: PizzaHAL,
     :param steps: int
                 How many steps for the fade (default: 100)
     """
-    hal.send_cmd(SerialCommands.BACKLIGHT if backlight else SerialCommands.FRONTLIGHT, 
-                 int(b * 255).to_bytes(1, 'little'),
-                 int(g * 255).to_bytes(1, 'little'),
-                 int(r * 255).to_bytes(1, 'little'),
-                 int(w * 255).to_bytes(1, 'little'), 
-                 int(fade * 1000).to_bytes(4, 'little'))
+    # TODO send light as bitmask
+    for l in iter(light):
+        hal.send_cmd(l, 
+                    int(b * 255).to_bytes(1, 'little'),
+                    int(g * 255).to_bytes(1, 'little'),
+                    int(r * 255).to_bytes(1, 'little'),
+                    int(w * 255).to_bytes(1, 'little'), 
+                    int(fade * 1000).to_bytes(4, 'little'))
 
 
 def play_sound(hal: PizzaHAL, sound: Any, **kwargs):
diff --git a/pizzactrl/statemachine.py b/pizzactrl/statemachine.py
index a7ae7c6..76dec7a 100644
--- a/pizzactrl/statemachine.py
+++ b/pizzactrl/statemachine.py
@@ -74,8 +74,9 @@ class Statemachine:
         self.state = State.POWER_ON
         self.hal = PizzaHAL()
 
-        self.chapter = 0
-        self.next_chapter = 0
+        self.chapter = 0            # The storyboard index of the current chapter to play
+        self.next_chapter = 0       # The storyboard index of the next chapter to play
+        self.chapter_set = False    # `True` if the next chapter has been set
 
         self.story = None
         self.story_de = story_de
@@ -214,6 +215,7 @@ class Statemachine:
             Continue in the Storyboard. Prepare advancing to the next chapter.
             """
             self.move = self.MOVE
+            self.chapter_set = True
             if len(self.story) > (self.chapter + 1):
                 self.next_chapter = self.chapter + 1
             else:
@@ -223,6 +225,7 @@ class Statemachine:
             """
             Repeat the current chapter. Do not rewind if the selection says so.
             """
+            self.chapter_set = True
             self.move = rewind
             self.next_chapter = self.chapter
         
@@ -230,10 +233,12 @@ class Statemachine:
             """
             Jump to a specified chapter.
             """
+            self.chapter_set = True
             self.move = self.MOVE
             self.next_chapter = next_chapter
 
         def _quit(**kwargs):
+            self.chapter_set = True
             self.move = self.MOVE
             self.loop = not shutdown
             self.next_chapter = None
@@ -273,7 +278,10 @@ class Statemachine:
                         logger.exception('Caught KeyError, ignoring...')
                         pass
             
-            self.next_chapter = self.chapter + 1
+            if not self.chapter_set:
+                self.chapter_set = True
+                self.next_chapter = self.chapter + 1
+
         else:
             self.next_chapter = None
     
@@ -282,7 +290,7 @@ class Statemachine:
         Update chapters and move the scrolls.
         Update self.chapter to self.next_chapter
         """
-        if self.next_chapter is not None:
+        if self.chapter_set and (self.next_chapter is not None):
             diff = self.next_chapter - self.chapter
             h_steps = 0
             v_steps = 0
@@ -315,16 +323,18 @@ class Statemachine:
                 move(self.hal, h_steps, True)
                 move(self.hal, v_steps, False)
 
+        logger.debug(f'Setting chapter (cur: {self.chapter}) to {self.next_chapter}.')
         self.chapter = self.next_chapter
+        self.chapter_set = False
 
     def _rewind(self):
         """
         Rewind all scrolls, post-process videos
         """
         # TODO postprocessing - add sound
-        logger.debug('Converting video...')
-        cmdstring = f'MP4Box -add {fs_names.REC_DRAW_CITY} {fs_names.REC_MERGED_VIDEO}'
-        call([cmdstring], shell=True)
+        # logger.debug('Converting video...')
+        # cmdstring = f'MP4Box -add {fs_names.REC_DRAW_CITY} {fs_names.REC_MERGED_VIDEO}'
+        # call([cmdstring], shell=True)
 
         logger.debug('Rewinding...')
         if self.move:
diff --git a/pizzactrl/statemachine_test.py b/pizzactrl/statemachine_test.py
new file mode 100644
index 0000000..3304a57
--- /dev/null
+++ b/pizzactrl/statemachine_test.py
@@ -0,0 +1,9 @@
+import sys
+import logging
+
+logging.basicConfig(level=logging.DEBUG, stream=sys.stdout)
+
+from pizzactrl.statemachine import Statemachine
+
+sm = Statemachine(move=True, loop=False, test=True)
+
diff --git a/pizzactrl/storyboard.py b/pizzactrl/storyboard.py
index a028aab..f9dc16f 100644
--- a/pizzactrl/storyboard.py
+++ b/pizzactrl/storyboard.py
@@ -1,5 +1,7 @@
 from enum import Enum, auto
 
+from pizzactrl.hal_serial import SerialCommands
+
 
 class Option(Enum):
     """
@@ -52,13 +54,13 @@ class Activity(Enum):
                       'b': 0,
                       'w': 1.0,
                       'fade': 1.0,
-                      'backlight': False}
+                      'light': [ SerialCommands.FRONTLIGHT ]}
     LIGHT_BACK =     {'r': 0,
                       'g': 0,
                       'b': 0,
                       'w': 1.0,
                       'fade': 1.0,
-                      'backlight': True}
+                      'light': [ SerialCommands.BACKLIGHT ]}
 
 
 class Do: