diff --git a/orchestrateur/main.py b/orchestrateur/main.py
index e7b4983..e9dea1b 100644
--- a/orchestrateur/main.py
+++ b/orchestrateur/main.py
@@ -113,7 +113,7 @@ def on_microwave_change(state: MicrowaveState, field: MicrowaveStateFields):
         if state.cooking_state in (CookingStates.DONE, CookingStates.STIRRING_REQUIRED, CookingStates.ALERT):
             # Trigger buzzer for user attention
             beats = 5 if state.cooking_state == CookingStates.ALERT else (1 if state.cooking_state == CookingStates.STIRRING_REQUIRED else 3)
-            buzzer.buzzer_siren(beatsNb=beats)
+            buzzer.buzzer_siren(beats_nb=beats)
         elif state.cooking_state == CookingStates.DONE and state.state == MicrowaveState.COOKING:
             state.set_state(MicrowaveState.DONE)
             print(f"[{state.microwave_id}] Cooking finished. Waiting for user to remove dish.")
@@ -275,17 +275,17 @@ async def rfid_listener_task():
                     TECHNICIAN_MODE = True
                     print(f"[RFID] Card {tag_id} VALIDATED! -> TECHNICIAN_MODE = TRUE")
                     # Optional: Sound positive feedback beep
-                    buzzer.buzzer_siren(beatsNb=1)
+                    buzzer.buzzer_siren(beats_nb=2)
                 else:
                     print(f"[RFID] Card {tag_id} REJECTED / Invalid.")
                     # Optional: Sound error feedback beep
-                    buzzer.buzzer_siren(beatsNb=2)
+                    buzzer.buzzer_siren(beats_nb=4)
 
         except Exception as e:
             print(f"[RFID Task] Error reading RFID tag: {e}")
 
         # Sleep 100ms between checks to keep CPU usage near zero
-        await asyncio.sleep(0.1)
+        await asyncio.sleep(0.2)
 
 async def display_broadcast_worker_task():
     """
diff --git a/orchestrateur/sensors/buzzer.py b/orchestrateur/sensors/buzzer.py
index 49f5d23..78770c8 100644
--- a/orchestrateur/sensors/buzzer.py
+++ b/orchestrateur/sensors/buzzer.py
@@ -1,33 +1,45 @@
 import time
+import threading
 import grovepi
 from sensors.lock import grove_lock
 from shared import config
 
-# Pin definition
-BUZZER_PIN = 8
+BUZZER_PIN = 8  # Must be a PWM pin on GrovePi (D3, D5, D6, D8 support analogWrite)
 
-grovepi.pinMode(BUZZER_PIN, "OUTPUT")
-buzzer_state = 0
+# Initialize pin mode
+try:
+    with grove_lock:
+        grovepi.pinMode(BUZZER_PIN, "OUTPUT")
+except Exception as e:
+    print(f"[BUZZER] Init error: {e}")
 
-def set_buzzer(state: int):
-    global buzzer_state
-    buzzer_state = state
+def _siren_worker(beats_nb: int, delay: float):
     if not config.BUZZER_ACTIVATED:
         return
-    try:
-        with grove_lock:
-            grovepi.digitalWrite(BUZZER_PIN, state)
-    except Exception as e:
-        print(f"[BUZZER] Error occurred while setting buzzer state: {e}")   
 
-def buzzer_toggle():
-    global buzzer_state
-    new_state = 1 - buzzer_state
-    set_buzzer(new_state)
-    
-def buzzer_siren(beatsNb: int = 3, delay: float = 0.3):
-    for _ in range(beatsNb):
-        set_buzzer(1)
-        time.sleep(delay)
-        set_buzzer(0)
-        time.sleep(delay)
\ No newline at end of file
+    with grove_lock:
+        try:
+            for _ in range(beats_nb):
+                # 1. Send single PWM write to start sound (Duty cycle ~128/255)
+                grovepi.analogWrite(BUZZER_PIN, 128)
+                time.sleep(delay)
+                
+                # 2. Send single PWM write to kill sound
+                grovepi.analogWrite(BUZZER_PIN, 0)
+                time.sleep(delay)
+        except Exception as e:
+            print(f"[BUZZER] Error during siren execution: {e}")
+        finally:
+            # Absolute safety reset
+            try:
+                grovepi.analogWrite(BUZZER_PIN, 0)
+                grovepi.digitalWrite(BUZZER_PIN, 0)
+            except Exception:
+                pass
+
+def buzzer_siren(beats_nb: int = 3, delay: float = 0.2, async_run: bool = True):
+    if async_run:
+        thread = threading.Thread(target=_siren_worker, args=(beats_nb, delay), daemon=True)
+        thread.start()
+    else:
+        _siren_worker(beats_nb, delay)
\ No newline at end of file
diff --git a/orchestrateur/sensors/camera.py b/orchestrateur/sensors/camera.py
index b38bcd1..52e7aef 100644
--- a/orchestrateur/sensors/camera.py
+++ b/orchestrateur/sensors/camera.py
@@ -1,6 +1,3 @@
-import grovepi
-import math
-from sensors.lock import grove_lock
 from picamera2 import Picamera2, Preview
 import time