Asset pools not getting created
Both video pools and sound pools are not getting created, however image pools are working just fine (when all are specified in a configuration file).

diff --git a/mpf/core/assets.py b/mpf/core/assets.py
index 4b2c38699..fc089e6de 100644
--- a/mpf/core/assets.py
+++ b/mpf/core/assets.py
@@ -458,13 +458,11 @@ class AssetManager(object):
         for ac in [x for x in self._asset_classes
                    if x['pool_config_section']]:
 
-            if (ac['pool_config_section']) not in config:
-                return
-
-            for name, settings in config[ac['pool_config_section']].items():
-                getattr(self.machine, ac['attribute'])[name] = (
-                    ac['cls'].asset_group_class(self.machine, name, settings,
-                                                ac['cls']))
+            if (ac['pool_config_section']) in config:
+                for name, settings in config[ac['pool_config_section']].items():
+                    getattr(self.machine, ac['attribute'])[name] = (
+                        ac['cls'].asset_group_class(self.machine, name, settings,
+                                                    ac['cls']))
 
     def _load_mode_assets(self, config, priority, mode):
         # Called on mode start to load the assets that are set to automatically
diff --git a/mpf/core/config_validator.py b/mpf/core/config_validator.py
index 587bc7544..cb352fc5d 100644
--- a/mpf/core/config_validator.py
+++ b/mpf/core/config_validator.py
@@ -780,7 +780,6 @@ smartmatrix:
 sound_player:
     __valid_in__: machine, mode, show
     action: single|enum(play,stop)|play
-    track: single|str|None
     volume: single|gain|None
     loops: single|int|None
     priority: single|int|None
@@ -803,6 +802,8 @@ sounds:
     loops: single|int|0
     priority: single|int|0
     max_queue_time: single|secs|None
+    events_when_played: list|str|None
+    events_when_stopped: list|str|None
     ducking:
         target: single|str|
         delay: single|str|0
['mpf/core/assets.py', 'mpf/core/config_validator.py']