diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index d88babb..0b97e4d 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -28,12 +28,16 @@ pub fn run() {
         .on_window_event(|window, event| {
             // 2. Terminate sidecar khi DAW window dong — tranh orphan process
             if let tauri::WindowEvent::Destroyed = event {
-                let state = window.state::<EngineProcess>();
-                if let Ok(mut lock) = state.0.lock() {
-                    if let Some(child) = lock.take() {
-                        let _ = child.kill();
-                        println!("daw_engine sidecar terminated.");
-                    }
+                // Lay child ra khoi lock, guard drop ngay tai day (trach E0597)
+                let child = window
+                    .state::<EngineProcess>()
+                    .0
+                    .lock()
+                    .ok()
+                    .and_then(|mut lock| lock.take());
+                if let Some(child) = child {
+                    let _ = child.kill();
+                    println!("daw_engine sidecar terminated.");
                 }
             }
         })