Fix play sometimes stopping almost immediately

app/config.py

@@ -67,6 +67,7 @@ class Config(object):
     MINIMUM_ROW_HEIGHT = 30
     MYSQL_CONNECT = os.environ.get('MYSQL_CONNECT') or "mysql+mysqldb://musicmuster:musicmuster@localhost/musicmuster_v2"  # noqa E501
     NOTE_TIME_FORMAT = "%H:%M:%S"
+    PLAY_SETTLE = 500000
     ROOT = os.environ.get('ROOT') or "/home/kae/music"
     IMPORT_DESTINATION = os.path.join(ROOT, "Singles")
     SCROLL_TOP_MARGIN = 3

app/musicmuster.py

@@ -1613,7 +1613,14 @@ class Window(QMainWindow, Ui_MainWindow):
             return
 
         # If track is playing, update track clocks time and colours
-        if self.music.player and self.music.player.is_playing():
+        # There is a discrete time between starting playing a track and
+        # player.is_playing() returning True, so assume playing if less
+        # than Config.PLAY_SETTLE microseconds have passed since
+        # starting play.
+        if self.music.player and self.current_track.start_time and (
+                self.music.player.is_playing() or
+                (datetime.now() - self.current_track.start_time)
+                < timedelta(microseconds=Config.PLAY_SETTLE)):
             playtime = self.music.get_playtime()
             time_to_fade = (self.current_track.fade_at - playtime)
             time_to_silence = (