diff --git a/homeassistant/components/zwave_js/siren.py b/homeassistant/components/zwave_js/siren.py
index 4ef89b9f4cd..a3fe3dfd595 100644
--- a/homeassistant/components/zwave_js/siren.py
+++ b/homeassistant/components/zwave_js/siren.py
@@ -68,8 +68,10 @@ class ZwaveSirenEntity(ZWaveBaseEntity, SirenEntity):
             self._attr_supported_features |= SUPPORT_TONES
 
     @property
-    def is_on(self) -> bool:
+    def is_on(self) -> bool | None:
         """Return whether device is on."""
+        if self.info.primary_value.value is None:
+            return None
         return bool(self.info.primary_value.value)
 
     async def async_set_value(
diff --git a/tests/components/zwave_js/test_siren.py b/tests/components/zwave_js/test_siren.py
index ebe437eb981..b1f7724316a 100644
--- a/tests/components/zwave_js/test_siren.py
+++ b/tests/components/zwave_js/test_siren.py
@@ -3,7 +3,7 @@ from zwave_js_server.event import Event
 
 from homeassistant.components.siren import ATTR_TONE, ATTR_VOLUME_LEVEL
 from homeassistant.components.siren.const import ATTR_AVAILABLE_TONES
-from homeassistant.const import STATE_OFF, STATE_ON
+from homeassistant.const import STATE_OFF, STATE_ON, STATE_UNKNOWN
 
 SIREN_ENTITY = "siren.indoor_siren_6_2"
 
@@ -65,7 +65,7 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
     state = hass.states.get(SIREN_ENTITY)
 
     assert state
-    assert state.state == STATE_OFF
+    assert state.state == STATE_UNKNOWN
     assert state.attributes.get(ATTR_AVAILABLE_TONES) == {
         0: "off",
         1: "01DING~1 (5 sec)",
@@ -117,6 +117,29 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
 
     client.async_send_command.reset_mock()
 
+    # Test value update from value updated event
+    event = Event(
+        type="value updated",
+        data={
+            "source": "node",
+            "event": "value updated",
+            "nodeId": node.node_id,
+            "args": {
+                "commandClassName": "Sound Switch",
+                "commandClass": 121,
+                "endpoint": 2,
+                "property": "toneId",
+                "newValue": 255,
+                "prevValue": None,
+                "propertyName": "toneId",
+            },
+        },
+    )
+    node.receive_event(event)
+
+    state = hass.states.get(SIREN_ENTITY)
+    assert state.state == STATE_ON
+
     # Test turn on with specific tone name and volume level
     await hass.services.async_call(
         "siren",
@@ -133,7 +156,7 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
     args = client.async_send_command.call_args[0][0]
     assert args["command"] == "node.set_value"
     assert args["nodeId"] == node.node_id
-    assert args["valueId"] == TONE_ID_VALUE_ID
+    assert args["valueId"] == {**TONE_ID_VALUE_ID, "value": 255}
     assert args["value"] == 1
     assert args["options"] == {"volume": 50}
 
@@ -155,7 +178,7 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
     args = client.async_send_command.call_args[0][0]
     assert args["command"] == "node.set_value"
     assert args["nodeId"] == node.node_id
-    assert args["valueId"] == TONE_ID_VALUE_ID
+    assert args["valueId"] == {**TONE_ID_VALUE_ID, "value": 255}
     assert args["value"] == 1
     assert args["options"] == {"volume": 50}
 
@@ -173,7 +196,7 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
     args = client.async_send_command.call_args[0][0]
     assert args["command"] == "node.set_value"
     assert args["nodeId"] == node.node_id
-    assert args["valueId"] == TONE_ID_VALUE_ID
+    assert args["valueId"] == {**TONE_ID_VALUE_ID, "value": 255}
     assert args["value"] == 0
 
     client.async_send_command.reset_mock()
@@ -190,8 +213,8 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
                 "commandClass": 121,
                 "endpoint": 2,
                 "property": "toneId",
-                "newValue": 255,
-                "prevValue": 0,
+                "newValue": 0,
+                "prevValue": 255,
                 "propertyName": "toneId",
             },
         },
@@ -199,4 +222,4 @@ async def test_siren(hass, client, aeotec_zw164_siren, integration):
     node.receive_event(event)
 
     state = hass.states.get(SIREN_ENTITY)
-    assert state.state == STATE_ON
+    assert state.state == STATE_OFF