diff --git a/photobooth_pygame.py b/photobooth_pygame.py
index 81fcd2c..2dfa2b7 100644
--- a/photobooth_pygame.py
+++ b/photobooth_pygame.py
@@ -91,6 +91,30 @@ THEMES = {
     },
 }
 
+# ── Utilitaire USB ───────────────────────────────────────────────────────────
+def _usb_reset_done():
+    """Reset USB des DSLR Canon/Nikon/Sony pour libérer tout claim obsolète."""
+    import glob, subprocess as _sp
+    for dev_path in glob.glob('/sys/bus/usb/devices/[0-9]*-[0-9.]*'):
+        prod_file = f"{dev_path}/product"
+        if not os.path.exists(prod_file):
+            continue
+        try:
+            prod = open(prod_file).read().strip()
+        except:
+            continue
+        if not any(b in prod for b in ('Canon', 'Nikon', 'Sony', 'Digital Camera')):
+            continue
+        try:
+            bus = int(open(f"{dev_path}/busnum").read().strip())
+            dev = int(open(f"{dev_path}/devnum").read().strip())
+            usb_path = f"/dev/bus/usb/{bus:03d}/{dev:03d}"
+            _sp.run(['sudo', 'usbreset', usb_path], capture_output=True, timeout=5)
+            print(f"USB reset: {usb_path} ({prod})")
+            time.sleep(1.2)
+        except Exception as e:
+            print(f"USB reset err: {e}")
+
 # ── États ────────────────────────────────────────────────────────────────────
 S_ACCUEIL = "accueil"
 S_MODE    = "mode"
@@ -528,6 +552,7 @@ class PB:
         self.sim = "--sim" in sys.argv
         self.cam = None
         if not self.sim:
+            _usb_reset_done()  # libère tout claim USB obsolète avant init
             for i in range(3):
                 try:
                     self.cam = gp.Camera(); self.cam.init()
@@ -715,9 +740,10 @@ class PB:
     def _cam_loop(self):
         errs = 0
         while True:
-            # En simulation : tentative de connexion automatique toutes les 8s
+            # En simulation : tentative de connexion automatique toutes les 10s
             if self.sim:
-                time.sleep(8)
+                time.sleep(10)
+                _usb_reset_done()
                 for _ in range(2):
                     try:
                         c = gp.Camera(); c.init()
@@ -727,7 +753,9 @@ class PB:
                         self.cam = c; self.sim = False; self.prev_actif = True
                         print("DSLR détecté automatiquement")
                         break
-                    except: time.sleep(1)
+                    except Exception as e:
+                        print(f"Auto-detect caméra: {e}")
+                        time.sleep(1)
                 continue
             if self.prev_actif:
                 try: