diff --git a/ch32v-insert-coin/src/app.rs b/ch32v-insert-coin/src/app.rs
index 1599599..1d5d0f3 100644
--- a/ch32v-insert-coin/src/app.rs
+++ b/ch32v-insert-coin/src/app.rs
@@ -550,22 +550,16 @@ impl App {
     pub fn shut_down(&mut self) {
         self.interfaces
             .pwm_core
-            .disable(ch32_hal::timer::Channel::Ch1);
+            .write_amplitude(self.services.led0.channel, 0);
         self.interfaces
             .pwm_core
-            .disable(ch32_hal::timer::Channel::Ch2);
-        self.interfaces
-            .pwm_core
-            .disable(ch32_hal::timer::Channel::Ch3);
-        self.interfaces
-            .pwm_core
-            .disable(ch32_hal::timer::Channel::Ch4);
+            .write_amplitude(self.services.led1.channel, 0);
+        crate::riscv::asm::delay(20_000_000);
 
         self.interfaces.pwm_core.pwm.borrow().shutdown();
         self.interfaces.adc_core.shutdown();
 
         self.interfaces.amp.disable();
-        crate::riscv::asm::delay(20_000_000);
     }
     pub fn volume_button(&mut self) {
         self.settings.volume.next();
@@ -629,7 +623,7 @@ impl App {
 
 // Events
 impl App {
-    fn main_button_click(&mut self) {
+    pub fn main_button_click(&mut self) {
         // TODO
         #[cfg(feature = "enable_print")]
         println!("click");
diff --git a/ch32v-insert-coin/src/main.rs b/ch32v-insert-coin/src/main.rs
index 6370d78..ca5a9dd 100644
--- a/ch32v-insert-coin/src/main.rs
+++ b/ch32v-insert-coin/src/main.rs
@@ -268,10 +268,6 @@ fn app_main(mut p: hal::Peripherals) {
     let led1_pin = PwmPin::new_ch1::<0>(p.PD2);
     let led1_ch = hal::timer::Channel::Ch1;
 
-    // // LED2 output setup
-    // let led2_pin = PwmPin::new_ch2::<0>(p.PA1);
-    // let led2_ch = hal::timer::Channel::Ch2;
-
     // DAC output setup
     let dac_pin = PwmPin::new_ch4::<0>(p.PC4);
     // let dac_ch = hal::timer::Channel::Ch4;
@@ -290,14 +286,16 @@ fn app_main(mut p: hal::Peripherals) {
 
     pwm.set_polarity(led0_ch, OutputPolarity::ActiveHigh);
     pwm.set_polarity(led1_ch, OutputPolarity::ActiveLow);
+    let mut pwm_core = SimplePwmCore::new(pwm);
+    pwm_core.write_amplitude(led0_ch, 0);
+    pwm_core.write_amplitude(led1_ch, 0);
+
     // pwm.set_polarity(led2_ch, OutputPolarity::ActiveLow);
 
     let tick_rate_hz = 50000;
 
     let core_config = CoreConfig::new(tick_rate_hz);
 
-    let pwm_core = SimplePwmCore::new(pwm);
-
     // === input setup ===
 
     // adc
@@ -401,6 +399,17 @@ fn app_main(mut p: hal::Peripherals) {
 
     let mut app = App::new(app_config, app_services, app_sequences, app_interfaces);
 
+    let need_sound = unsafe {
+        #[allow(static_mut_refs)]
+        if INPUT_FLAGS.main_btn_flag.active() {
+            #[allow(static_mut_refs)]
+            INPUT_FLAGS.main_btn_flag.clear();
+            true
+        } else {
+            false
+        }
+    };
+
     // init systick
     systick_init(tick_rate_hz);
 
@@ -432,6 +441,9 @@ fn app_main(mut p: hal::Peripherals) {
     let mut light_ctrl_btn_prev = light_ctrl_btn_input.is_high_immediate();
 
     app.init();
+    if need_sound {
+        app.main_button_click();
+    }
     loop {
         // system servicing