don?t crash on stored playlists

mcg.py

@@ -267,6 +267,7 @@ class MCGClient(MCGBase, mpd.MPDClient):
 		album = None
 		pos = None
 		if song:
+			try:
 				hash = MCGAlbum.hash(song['album'], song['date'])
 				if hash in self._albums:
 					album = self._albums[hash]
@@ -276,6 +277,8 @@ class MCGClient(MCGBase, mpd.MPDClient):
 				if '/' in pos:
 					pos = pos[0: pos.index('/')]
 				pos = int(pos) - 1
+			except KeyError:
+				pass
 		self._state = state
 		self._callback(MCGClient.SIGNAL_STATUS, state, album, pos, volume, error)