diff --git a/mopidy/backends/spotify/__init__.py b/mopidy/backends/spotify/__init__.py
index d85e91b2..021277f2 100644
--- a/mopidy/backends/spotify/__init__.py
+++ b/mopidy/backends/spotify/__init__.py
@@ -61,7 +61,9 @@ class SpotifyBackend(ThreadingActor, Backend):
 
         self.uri_handlers = [u'spotify:', u'http://open.spotify.com/']
 
-        # TODO-PYKKA: Do setup after actor starts?
+        self.spotify = None
+
+    def post_start(self):
         self.spotify = self._connect()
 
     def _connect(self):
diff --git a/mopidy/frontends/lastfm.py b/mopidy/frontends/lastfm.py
index f8a46c0f..4a703c22 100644
--- a/mopidy/frontends/lastfm.py
+++ b/mopidy/frontends/lastfm.py
@@ -41,10 +41,7 @@ class LastfmFrontend(ThreadingActor, BaseFrontend):
         self.lastfm = None
         self.last_start_time = None
 
-        # TODO-PYKKA: Do setup after actor starts
-        self._setup()
-
-    def _setup(self):
+    def post_start(self):
         try:
             username = settings.LASTFM_USERNAME
             password_hash = pylast.md5(settings.LASTFM_PASSWORD)
diff --git a/mopidy/frontends/mpd/__init__.py b/mopidy/frontends/mpd/__init__.py
index 3a1211ae..96500d9b 100644
--- a/mopidy/frontends/mpd/__init__.py
+++ b/mopidy/frontends/mpd/__init__.py
@@ -21,14 +21,12 @@ class MpdFrontend(ThreadingActor, BaseFrontend):
     """
 
     def __init__(self):
-        # TODO-PYKKA: Do setup after actor starts?
+        self._thread = None
+
+    def post_start(self):
         self._thread = MpdThread()
         self._thread.start()
 
-    def destroy(self):
-        """Destroys the MPD server."""
-        self._thread.destroy()
-
 
 class MpdThread(BaseThread):
     def __init__(self):
diff --git a/mopidy/mixers/denon.py b/mopidy/mixers/denon.py
index 36f0f3bd..832e7d1a 100644
--- a/mopidy/mixers/denon.py
+++ b/mopidy/mixers/denon.py
@@ -25,21 +25,16 @@ class DenonMixer(ThreadingActor, BaseMixer):
     - :attr:`mopidy.settings.MIXER_EXT_PORT` -- Example: ``/dev/ttyUSB0``
     """
 
-    def __init__(self):
-        """
-        Connects using the serial specifications from Denon's RS-232 Protocol
-        specification: 9600bps 8N1.
-        """
-        # TODO-PYKKA: Do setup after actor starts?
-        device = kwargs.get('device', None)
-        if device:
-            self._device = device
-        else:
-            from serial import Serial
-            self._device = Serial(port=settings.MIXER_EXT_PORT, timeout=0.2)
+    def __init__(self, *args, **kwargs):
+        self._device = kwargs.get('device', None)
         self._levels = ['99'] + ["%(#)02d" % {'#': v} for v in range(0, 99)]
         self._volume = 0
 
+    def post_start(self):
+        if self._device is None:
+            from serial import Serial
+            self._device = Serial(port=settings.MIXER_EXT_PORT, timeout=0.2)
+
     def _get_volume(self):
         self._ensure_open_device()
         self._device.write('MV?\r')
diff --git a/mopidy/mixers/nad.py b/mopidy/mixers/nad.py
index 2844f579..e12b8b92 100644
--- a/mopidy/mixers/nad.py
+++ b/mopidy/mixers/nad.py
@@ -75,10 +75,7 @@ class NadTalker(ThreadingActor):
     def __init__(self):
         self._device = None
 
-        # TODO-PYKKA: Do after actor starts?
-        self._setup()
-
-    def _setup(self):
+    def post_start(self):
         self._open_connection()
         self._set_device_to_known_state()
 
diff --git a/mopidy/outputs/gstreamer.py b/mopidy/outputs/gstreamer.py
index b0b98d99..2a3d9adc 100644
--- a/mopidy/outputs/gstreamer.py
+++ b/mopidy/outputs/gstreamer.py
@@ -24,7 +24,7 @@ class GStreamerOutput(ThreadingActor, BaseOutput):
     def __init__(self):
         self.gst_pipeline = None
 
-        # TODO-PYKKA: Run setup after actor starts?
+    def post_start(self):
         self._setup_gstreamer()
 
     def _setup_gstreamer(self):