diff --git a/custom_components/crestron/media_player.py b/custom_components/crestron/media_player.py
index 904dfac..0d998d7 100644
--- a/custom_components/crestron/media_player.py
+++ b/custom_components/crestron/media_player.py
@@ -151,16 +151,27 @@ def source(self) -> str | None:
 
     # --- Commands ---------------------------------------------------------
 
+    def _apply_optimistic(self, updates: dict[str, Any]) -> None:
+        data = dict(self.coordinator.data or {})
+        zone_state = dict(data.get(self._zone, {}))
+        zone_state.update(updates)
+        data[self._zone] = zone_state
+        self.coordinator.async_set_updated_data(data)
+
     async def async_turn_on(self) -> None:
         await self._hub.command(f"{self._zone} ON")
+        self._apply_optimistic({"power": f"{self._zone} POWER ON"})
         await self.coordinator.async_request_refresh()
 
     async def async_turn_off(self) -> None:
         await self._hub.command(f"{self._zone} OFF")
+        self._apply_optimistic({"power": f"{self._zone} POWER OFF"})
         await self.coordinator.async_request_refresh()
 
     async def async_set_volume_level(self, volume: float) -> None:
-        await self._hub.command(f"{self._zone} VOLUME SET {round(volume * 100)}")
+        level = round(volume * 100)
+        await self._hub.command(f"{self._zone} VOLUME SET {level}")
+        self._apply_optimistic({"volume": level})
         await self.coordinator.async_request_refresh()
 
     async def async_volume_up(self) -> None:
@@ -182,4 +193,7 @@ async def async_select_source(self, source: str) -> None:
             _LOGGER.warning("Unknown Crestron source: %s", source)
             return
         await self._hub.command(f"{self._zone} {code}")
+        self._apply_optimistic(
+            {"power": f"{self._zone} POWER ON", "source": code}
+        )
         await self.coordinator.async_request_refresh()
diff --git a/tests/test_media_player.py b/tests/test_media_player.py
index fc586aa..542b8e2 100644
--- a/tests/test_media_player.py
+++ b/tests/test_media_player.py
@@ -21,6 +21,11 @@ def _make_hub(zone_data: dict | None = None) -> MagicMock:
     hub.coordinator.last_update_success = True
     hub.coordinator.async_request_refresh = AsyncMock()
     hub.coordinator.async_add_listener = MagicMock()
+
+    def _set(new_data: dict) -> None:
+        hub.coordinator.data = new_data
+
+    hub.coordinator.async_set_updated_data = MagicMock(side_effect=_set)
     return hub
 
 
@@ -114,3 +119,37 @@ async def test_async_select_unknown_source_is_noop() -> None:
     zone = CrestronZone(hub, "KITCHEN")
     await zone.async_select_source("Bogus")
     hub.command.assert_not_awaited()
+
+
+async def test_turn_on_optimistically_updates_state() -> None:
+    hub = _make_hub({"power": "KITCHEN POWER OFF"})
+    zone = CrestronZone(hub, "KITCHEN")
+    await zone.async_turn_on()
+    assert hub.coordinator.data["KITCHEN"]["power"].endswith("ON")
+    assert zone.state == MediaPlayerState.ON
+
+
+async def test_turn_off_optimistically_updates_state() -> None:
+    hub = _make_hub({"power": "KITCHEN POWER ON"})
+    zone = CrestronZone(hub, "KITCHEN")
+    await zone.async_turn_off()
+    assert hub.coordinator.data["KITCHEN"]["power"].endswith("OFF")
+    assert zone.state == MediaPlayerState.OFF
+
+
+async def test_set_volume_optimistically_updates_level() -> None:
+    hub = _make_hub({"power": "KITCHEN POWER ON"})
+    zone = CrestronZone(hub, "KITCHEN")
+    await zone.async_set_volume_level(0.25)
+    assert hub.coordinator.data["KITCHEN"]["volume"] == 25
+    assert zone.volume_level == 0.25
+
+
+async def test_select_source_optimistically_updates_source_and_power() -> None:
+    hub = _make_hub({"power": "KITCHEN POWER OFF"})
+    zone = CrestronZone(hub, "KITCHEN")
+    await zone.async_select_source("Chromecast")
+    assert hub.coordinator.data["KITCHEN"]["source"] == "CHROMECAST"
+    assert hub.coordinator.data["KITCHEN"]["power"].endswith("ON")
+    assert zone.source == "Chromecast"
+    assert zone.state == MediaPlayerState.ON