diff --git a/core/communication/websocket.py b/core/communication/websocket.py
index 4e40d2a..e53096a 100644
--- a/core/communication/websocket.py
+++ b/core/communication/websocket.py
@@ -539,7 +539,7 @@ class WebSocketHandler:
     async def _handle_set_session_id(self, message: SetSessionIdMessage) -> None:
         """Handle setSessionId message."""
         display_identifier = message.payload.displayIdentifier
-        session_id = message.payload.sessionId
+        session_id = str(message.payload.sessionId) if message.payload.sessionId is not None else None
 
         logger.info(f"[RX Processing] setSessionId for display {display_identifier}: {session_id}")
 
diff --git a/core/streaming/manager.py b/core/streaming/manager.py
index 5b4637c..e2f02d9 100644
--- a/core/streaming/manager.py
+++ b/core/streaming/manager.py
@@ -380,6 +380,8 @@ class StreamManager:
 
     def set_session_id(self, display_id: str, session_id: str):
         """Set session ID for tracking integration."""
+        # Ensure session_id is always a string for consistent type handling
+        session_id = str(session_id) if session_id is not None else None
         with self._lock:
             for subscription_info in self._subscriptions.values():
                 # Check if this subscription matches the display_id
diff --git a/core/tracking/integration.py b/core/tracking/integration.py
index 3f1ebe0..8c96750 100644
--- a/core/tracking/integration.py
+++ b/core/tracking/integration.py
@@ -474,6 +474,8 @@ class TrackingPipelineIntegration:
             display_id: Display identifier
             session_id: Session identifier
         """
+        # Ensure session_id is always a string for consistent type handling
+        session_id = str(session_id) if session_id is not None else None
         self.active_sessions[display_id] = session_id
         logger.info(f"Set session {session_id} for display {display_id}")