diff --git a/homeassistant/components/sonos/diagnostics.py b/homeassistant/components/sonos/diagnostics.py
index e2949b8689c..6d5a7fff7a1 100644
--- a/homeassistant/components/sonos/diagnostics.py
+++ b/homeassistant/components/sonos/diagnostics.py
@@ -21,20 +21,24 @@ MEDIA_DIAGNOSTIC_ATTRIBUTES = (
     "source_name",
     "title",
     "uri",
-    "_last_event_variables",
 )
 SPEAKER_DIAGNOSTIC_ATTRIBUTES = (
     "available",
     "battery_info",
+    "hardware_version",
     "household_id",
     "is_coordinator",
     "model_name",
+    "model_number",
+    "software_version",
     "sonos_group_entities",
     "subscription_address",
     "subscriptions_failed",
+    "version",
     "zone_name",
     "_group_members_missing",
     "_last_activity",
+    "_last_event_cache",
 )
 
 
@@ -52,8 +56,7 @@ async def async_get_config_entry_diagnostics(
             continue
         for key, value in data.items():
             if isinstance(value, SonosSpeaker):
-                speaker_info = await async_generate_speaker_info(hass, value)
-                payload[section][key] = speaker_info
+                payload[section][key] = await async_generate_speaker_info(hass, value)
             else:
                 payload[section][key] = value
 
@@ -66,21 +69,8 @@ async def async_generate_media_info(
     """Generate a diagnostic payload for current media metadata."""
     payload = {}
 
-    def get_contents(item):
-        if isinstance(item, (int, float, str)):
-            return item
-        if isinstance(item, dict):
-            payload = {}
-            for key, value in item.items():
-                payload[key] = get_contents(value)
-            return payload
-        if hasattr(item, "__dict__"):
-            return vars(item)
-        return item
-
     for attrib in MEDIA_DIAGNOSTIC_ATTRIBUTES:
-        value = getattr(speaker.media, attrib)
-        payload[attrib] = get_contents(value)
+        payload[attrib] = getattr(speaker.media, attrib)
 
     def poll_current_track_info():
         return speaker.soco.avTransport.GetPositionInfo(
@@ -99,7 +89,22 @@ async def async_generate_speaker_info(
 ) -> dict[str, Any]:
     """Generate the diagnostic payload for a specific speaker."""
     payload = {}
+
+    def get_contents(item):
+        if isinstance(item, (int, float, str)):
+            return item
+        if isinstance(item, dict):
+            payload = {}
+            for key, value in item.items():
+                payload[key] = get_contents(value)
+            return payload
+        if hasattr(item, "__dict__"):
+            return vars(item)
+        return item
+
     for attrib in SPEAKER_DIAGNOSTIC_ATTRIBUTES:
-        payload[attrib] = getattr(speaker, attrib)
+        value = getattr(speaker, attrib)
+        payload[attrib] = get_contents(value)
+
     payload["media"] = await async_generate_media_info(hass, speaker)
     return payload
diff --git a/homeassistant/components/sonos/speaker.py b/homeassistant/components/sonos/speaker.py
index cf829a890e0..ac5a07f2204 100644
--- a/homeassistant/components/sonos/speaker.py
+++ b/homeassistant/components/sonos/speaker.py
@@ -123,7 +123,6 @@ class SonosMedia:
 
         self.position: float | None = None
         self.position_updated_at: datetime.datetime | None = None
-        self._last_event_variables: dict[str, Any] | None = None
 
     def clear(self) -> None:
         """Clear basic media info."""
@@ -164,6 +163,7 @@ class SonosSpeaker:
         self._resubscription_lock: asyncio.Lock | None = None
         self._event_dispatchers: dict[str, Callable] = {}
         self._last_activity: float = NEVER_TIME
+        self._last_event_cache: dict[str, Any] = {}
 
         # Scheduled callback handles
         self._poll_timer: Callable | None = None
@@ -172,8 +172,11 @@ class SonosSpeaker:
         self.dispatchers: list[Callable] = []
 
         # Device information
+        self.hardware_version = speaker_info["hardware_version"]
+        self.software_version = speaker_info["software_version"]
         self.mac_address = speaker_info["mac_address"]
         self.model_name = speaker_info["model_name"]
+        self.model_number = speaker_info["model_number"]
         self.uid = speaker_info["uid"]
         self.version = speaker_info["display_version"]
         self.zone_name = speaker_info["zone_name"]
@@ -427,6 +430,9 @@ class SonosSpeaker:
         dispatcher = self._event_dispatchers[event.service.service_type]
         dispatcher(event)
 
+        # Save most recent event variables for diagnostics
+        self._last_event_cache[event.service.service_type] = event.variables
+
     @callback
     def async_dispatch_alarms(self, event: SonosEvent) -> None:
         """Add the soco instance associated with the event to the callback."""
@@ -1003,12 +1009,6 @@ class SonosSpeaker:
         if new_status == SONOS_STATE_TRANSITIONING:
             return
 
-        if variables:
-            # Store for diagnostics
-            self.media._last_event_variables = (  # pylint: disable=protected-access
-                variables
-            )
-
         self.media.clear()
         update_position = new_status != self.media.playback_status
         self.media.playback_status = new_status
diff --git a/tests/components/sonos/conftest.py b/tests/components/sonos/conftest.py
index a35eee1c1b3..2da2d79ba99 100644
--- a/tests/components/sonos/conftest.py
+++ b/tests/components/sonos/conftest.py
@@ -206,6 +206,8 @@ def speaker_info_fixture():
         "zone_name": "Zone A",
         "uid": "RINCON_test",
         "model_name": "Model Name",
+        "model_number": "S12",
+        "hardware_version": "1.20.1.6-1.1",
         "software_version": "49.2-64250",
         "mac_address": "00-11-22-33-44-55",
         "display_version": "13.1",