diff --git a/rpi/controllers/mqtt_forwarder.py b/rpi/controllers/mqtt_forwarder.py
index 64b557bb..e95c3d93 100644
--- a/rpi/controllers/mqtt_forwarder.py
+++ b/rpi/controllers/mqtt_forwarder.py
@@ -6,22 +6,24 @@ from services.mqtt_service import MQTTService
 
 class MQTTForwarder:
 
-    client_id : str
-    local_broker : MQTTService
-    central_broker : MQTTService
+    _client_id : str
+    _local_broker : MQTTService
+    _central_broker : MQTTService
+    _qos : int
 
-    def __init__(self, client_id : str, src_mqtt: MQTTService, dst_mqtt: MQTTService):
-        self.client_id = client_id
-        self.local_broker = src_mqtt
-        self.central_broker = dst_mqtt
+    def __init__(self, client_id : str, src_mqtt: MQTTService, dst_mqtt: MQTTService, qos : int):
+        self._client_id = client_id
+        self._local_broker = src_mqtt
+        self._central_broker = dst_mqtt
+        self._qos = qos
 
     def start(self, src_topic: str, dst_topic: str):
         try:
             def forward_handler(topic: str, msg: str):
                 forwarded_msg = self.__wrap_data(msg)
-                self.central_broker.publish(dst_topic, forwarded_msg)
+                self._central_broker.publish(dst_topic, forwarded_msg, self._qos)
 
-            self.local_broker.subscribe(src_topic, forward_handler)
+            self._local_broker.subscribe(src_topic, forward_handler)
         except Exception as e:
             print(f"An error occurred while forwarding from {src_topic} to {dst_topic}: {e}")
 
@@ -30,7 +32,7 @@ class MQTTForwarder:
         result = {}
         data = json.loads(msg)
         result["timestamp"] = int(time.time())
-        result["systemId"] = self.client_id
+        result["systemId"] = self._client_id
         result["data"] = {}
         for keys in data:
             result["data"][keys] = data[keys]
diff --git a/rpi/hardware/sound/sound.py b/rpi/hardware/sound/sound.py
index 8bb5e663..f23625d5 100644
--- a/rpi/hardware/sound/sound.py
+++ b/rpi/hardware/sound/sound.py
@@ -9,11 +9,10 @@ class SoundReader:
     _pin :int
     _running :bool
     _thread :threading.Thread | None
-    _subscriber :Callable[[int], None]
+    _subscriber :Callable[[str], None]
 
     def __init__(self, pin):
         self._pin = pin
-        self._sound_level = 0
         self._running = False
         self._thread = None
 
@@ -32,15 +31,12 @@ class SoundReader:
             self._thread.join()
         GPIO.cleanup()
 
-    def subscribe(self, handler:Callable[[int], None]):
+    def subscribe(self, handler:Callable[[str], None]):
         self._subscriber = handler
 
-    def get_level(self):
-        return self._sound_level
-
-    def _notify(self):
+    def _notify(self, data : str):
         if self._subscriber:
-            self._subscriber(self._sound_level)
+            self._subscriber(data)
 
     def _read(self):
         measure_duration = 0.2
@@ -51,7 +47,7 @@ class SoundReader:
             while time.time() - start < measure_duration:
                 if GPIO.input(self._pin):
                     level += 1
-            self._sound_level = level
+            self._notify(f'{{"soundSensorValue": {level}}}')
             time.sleep(interval - measure_duration)
 
 if __name__ == "__main__":