Introduce GSTREAMER_AUDIO_SINK setting to control which sink we use

mopidy/outputs/gstreamer.py

@@ -66,7 +66,7 @@ class GStreamerProcess(BaseProcess):
         self.gst_pipeline = gst.parse_launch(' ! '.join([
             'audioconvert name=convert',
             'volume name=volume',
-            'autoaudiosink'
+            settings.GSTREAMER_AUDIO_SINK,
         ]))
 
         pad = self.gst_pipeline.get_by_name('convert').get_pad('sink')

mopidy/settings.py

@@ -167,3 +167,8 @@ SPOTIFY_USERNAME = u''
 #:
 #: Used by :mod:`mopidy.backends.libspotify`.
 SPOTIFY_PASSWORD = u''
+
+#: Which GStreamer audio sink to use in output pipeline.
+#:
+#: Default: autoaudiosink
+GSTREAMER_AUDIO_SINK = u'autoaudiosink'