diff --git a/platypush/plugins/hid/__init__.py b/platypush/plugins/hid/__init__.py
index 6e33e8c3..7c9ac5fb 100644
--- a/platypush/plugins/hid/__init__.py
+++ b/platypush/plugins/hid/__init__.py
@@ -213,7 +213,6 @@ class HidPlugin(RunnablePlugin):
         for path in new_device_paths:
             device = scanned_devices[path]
             get_bus().post(HidDeviceConnectedEvent(**device))
-
             monitor_rule = self._get_monitor_rule(device)
             if monitor_rule:
                 self._register_device_monitor(device, monitor_rule)
@@ -227,7 +226,10 @@ class HidPlugin(RunnablePlugin):
         lost_device_paths = available_device_paths.difference(scanned_device_paths)
 
         for path in lost_device_paths:
-            get_bus().post(HidDeviceDisconnectedEvent(**self._available_devices[path]))
+            device = self._available_devices.get(path)
+            if device:
+                get_bus().post(HidDeviceDisconnectedEvent(**device))
+                self._unregister_device_monitor(device['path'])
 
     def _handle_device_events(self, scanned_devices: dict):
         """
diff --git a/platypush/schemas/hid.py b/platypush/schemas/hid.py
index 6cb372ca..3cfee402 100644
--- a/platypush/schemas/hid.py
+++ b/platypush/schemas/hid.py
@@ -50,7 +50,7 @@ class HidDeviceSchema(Schema):
 
 class HidMonitoredDeviceSchema(HidDeviceSchema):
     notify_only_if_changed = fields.Boolean(
-        missing=True,
+        load_default=True,
         metadata={
             'description': 'If set to true (default), only changes in the '
             'values of the device will trigger events. So if you are e.g. '
@@ -60,7 +60,7 @@ class HidMonitoredDeviceSchema(HidDeviceSchema):
     )
 
     data_size = fields.Integer(
-        missing=64,
+        load_default=64,
         metadata={
             'description': 'How many bytes should be read from the device on '
             'each iteration (default: 64)',
@@ -68,7 +68,7 @@ class HidMonitoredDeviceSchema(HidDeviceSchema):
     )
 
     poll_seconds = fields.Float(
-        missing=0,
+        load_default=0,
         metadata={
             'description': 'How often we should wait before data reads '
             '(default: no wait)'