Fix Insteon issue with dimmer default on level

homeassistant/components/insteon/insteon_entity.py

@@ -153,10 +153,9 @@ def _print_aldb(self):
 
     def get_device_property(self, name: str):
         """Get a single Insteon device property value (raw)."""
-        value = None
         if (prop := self._insteon_device.properties.get(name)) is not None:
-            value = prop.value if prop.new_value is None else prop.new_value
-        return value
+            return prop.value
+        return None
 
     def _get_label(self):
         """Get the device label for grouped devices."""

homeassistant/components/insteon/light.py

@@ -58,9 +58,9 @@ async def async_turn_on(self, **kwargs):
         """Turn light on."""
         if ATTR_BRIGHTNESS in kwargs:
             brightness = int(kwargs[ATTR_BRIGHTNESS])
-        else:
+        elif self._insteon_device_group.group == 1:
             brightness = self.get_device_property(ON_LEVEL)
-        if brightness is not None:
+        if brightness:
             await self._insteon_device.async_on(
                 on_level=brightness, group=self._insteon_device_group.group
             )