diff --git a/mopidy/frontends/lastfm.py b/mopidy/frontends/lastfm.py
index 125457cd..0e79024b 100644
--- a/mopidy/frontends/lastfm.py
+++ b/mopidy/frontends/lastfm.py
@@ -37,6 +37,7 @@ class LastfmFrontend(ThreadingActor, BackendListener):
     """
 
     def __init__(self):
+        super(LastfmFrontend, self).__init__()
         self.lastfm = None
         self.last_start_time = None
 
diff --git a/mopidy/frontends/mpd/__init__.py b/mopidy/frontends/mpd/__init__.py
index b6adc09d..99134012 100644
--- a/mopidy/frontends/mpd/__init__.py
+++ b/mopidy/frontends/mpd/__init__.py
@@ -25,6 +25,7 @@ class MpdFrontend(actor.ThreadingActor, listeners.BackendListener):
     """
 
     def __init__(self):
+        super(MpdFrontend, self).__init__()
         hostname = network.format_hostname(settings.MPD_SERVER_HOSTNAME)
         port = settings.MPD_SERVER_PORT
 
diff --git a/mopidy/frontends/mpris/__init__.py b/mopidy/frontends/mpris/__init__.py
index 579038ca..0f5d35c5 100644
--- a/mopidy/frontends/mpris/__init__.py
+++ b/mopidy/frontends/mpris/__init__.py
@@ -57,6 +57,7 @@ class MprisFrontend(ThreadingActor, BackendListener):
     """
 
     def __init__(self):
+        super(MprisFrontend, self).__init__()
         self.indicate_server = None
         self.mpris_object = None
 
diff --git a/mopidy/gstreamer.py b/mopidy/gstreamer.py
index b6a8ab2b..282acd4e 100644
--- a/mopidy/gstreamer.py
+++ b/mopidy/gstreamer.py
@@ -25,6 +25,7 @@ class GStreamer(ThreadingActor):
     """
 
     def __init__(self):
+        super(GStreamer, self).__init__()
         self._default_caps = gst.Caps("""
             audio/x-raw-int,
             endianness=(int)1234,
diff --git a/mopidy/mixers/alsa.py b/mopidy/mixers/alsa.py
index ae4bd031..acb12e66 100644
--- a/mopidy/mixers/alsa.py
+++ b/mopidy/mixers/alsa.py
@@ -23,6 +23,7 @@ class AlsaMixer(ThreadingActor, BaseMixer):
     """
 
     def __init__(self):
+        super(AlsaMixer, self).__init__()
         self._mixer = None
 
     def on_start(self):
diff --git a/mopidy/mixers/denon.py b/mopidy/mixers/denon.py
index d0dc5f54..e869dae8 100644
--- a/mopidy/mixers/denon.py
+++ b/mopidy/mixers/denon.py
@@ -26,6 +26,7 @@ class DenonMixer(ThreadingActor, BaseMixer):
     """
 
     def __init__(self, *args, **kwargs):
+        super(DenonMixer, self).__init__(*arg, **kwargs)
         self._device = kwargs.get('device', None)
         self._levels = ['99'] + ["%(#)02d" % {'#': v} for v in range(0, 99)]
         self._volume = 0
diff --git a/mopidy/mixers/dummy.py b/mopidy/mixers/dummy.py
index 23f96c4c..7262e83c 100644
--- a/mopidy/mixers/dummy.py
+++ b/mopidy/mixers/dummy.py
@@ -6,6 +6,7 @@ class DummyMixer(ThreadingActor, BaseMixer):
     """Mixer which just stores and reports the chosen volume."""
 
     def __init__(self):
+        super(DummyMixer, self).__init__()
         self._volume = None
 
     def get_volume(self):
diff --git a/mopidy/mixers/gstreamer_software.py b/mopidy/mixers/gstreamer_software.py
index 523c3387..a38692db 100644
--- a/mopidy/mixers/gstreamer_software.py
+++ b/mopidy/mixers/gstreamer_software.py
@@ -8,6 +8,7 @@ class GStreamerSoftwareMixer(ThreadingActor, BaseMixer):
     """Mixer which uses GStreamer to control volume in software."""
 
     def __init__(self):
+        super(GStreamerSoftwareMixer, self).__init__()
         self.output = None
 
     def on_start(self):
diff --git a/mopidy/mixers/nad.py b/mopidy/mixers/nad.py
index 4dbf27be..78473308 100644
--- a/mopidy/mixers/nad.py
+++ b/mopidy/mixers/nad.py
@@ -37,6 +37,7 @@ class NadMixer(ThreadingActor, BaseMixer):
     """
 
     def __init__(self):
+        super(NadMixer, self).__init__()
         self._volume_cache = None
         self._nad_talker = NadTalker.start().proxy()
 
@@ -71,6 +72,7 @@ class NadTalker(ThreadingActor):
     _nad_volume = None
 
     def __init__(self):
+        super(NadTalker, self).__init__()
         self._device = None
 
     def on_start(self):
diff --git a/mopidy/utils/network.py b/mopidy/utils/network.py
index 5079fe7c..0a0928ce 100644
--- a/mopidy/utils/network.py
+++ b/mopidy/utils/network.py
@@ -297,6 +297,7 @@ class LineProtocol(ThreadingActor):
     encoding = 'utf-8'
 
     def __init__(self, connection):
+        super(LineProtocol, self).__init__()
         self.connection = connection
         self.prevent_timeout = False
         self.recv_buffer = ''