1 files changed, 4 insertions, 2 deletions

diff --git a/helpers/music_file.py b/helpers/music_file.py
index f1aa341..f391ff4 100644
--- a/helpers/music_file.py
+++ b/helpers/music_file.py
@@ -7,6 +7,7 @@ import os.path
 
 from .lock import Lock
 from . import Config, gain
+from .mixer import Mixer
 
 file_lock = Lock("file")
 
@@ -31,6 +32,7 @@ class MusicFile(Machine):
 
         Machine.__init__(self, states=states, transitions=transitions, initial='initial')
 
+        self.mixer = mapping.mixer or Mixer()
         self.volume = 100
         self.mapping = mapping
         self.filename = filename
@@ -95,7 +97,7 @@ class MusicFile(Machine):
         self.start_playing()
 
     def on_enter_loaded_playing(self):
-        self.mapping.mixer.add_file(self)
+        self.mixer.add_file(self)
 
     def finished_callback(self):
         if self.is_loaded_playing():
@@ -104,7 +106,7 @@ class MusicFile(Machine):
             self.stopped()
 
     def trigger_stopped_events(self):
-        self.mapping.mixer.remove_file(self)
+        self.mixer.remove_file(self)
         self.wait_event.set()
 
     def play_callback(self, out_data_length, frame_count):