diff --git a/include/main.h b/include/main.h
index cf1af1e..8f0ef5c 100644
--- a/include/main.h
+++ b/include/main.h
@@ -17,7 +17,7 @@
 #define KEY_DST GPIO_NUM_17  // D8
 
 // Buzzer
-#define BUZZER GPIO_NUM_0    // ! B1  <-> LED green
+#define BUZZER GPIO_NUM_43   // TX
 #define LEDC_CHANNEL 0
 #define LEDC_TIMER_8_BIT 8
 #define LEDC_BASE_FREQ 5000
diff --git a/src/main.cpp b/src/main.cpp
index 12a2289..7cfb86a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -287,17 +287,15 @@ void setup() {
     digitalWrite(LED_USER, LOW);
 
     // Buzzer
-    /*
     ledcSetup(LEDC_CHANNEL, LEDC_BASE_FREQ, LEDC_TIMER_8_BIT);
     ledcAttachPin(BUZZER, LEDC_CHANNEL);
     // Test tone while booting
-    if (ledcWriteTone(BUZZER, 4000) == 0) {
+    if (ledcWriteTone(LEDC_CHANNEL, 4000) == 0) {
         Serial.println("Error setting buzzer tone");
     } else {
         delay(750);
-        ledcWriteTone(BUZZER, 0); // Buzzer off
+        ledcWriteTone(LEDC_CHANNEL, 0); // Buzzer off
     }
-    */
 
     // Startup sequence: test all led and short beep buzzer
 
@@ -374,6 +372,25 @@ void setup() {
 
 }
 
+void atariKeyclick() {
+/*
+ * Anderer 12V-fähiger Buzzer!
+ * 
+    Buzzer + → 12V
+    Buzzer – → IRLZ44N Drain
+    IRLZ44N Source → GND
+    ESP32 GPIO43 → 1kΩ resistor → Gate
+    ESP32 GND must be connected to the same GND as the 12V supply.
+ * */
+  ledcWriteTone(LEDC_CHANNEL, 3200);
+  delayMicroseconds(3000);
+  ledcWriteTone(LEDC_CHANNEL, 0);
+  delayMicroseconds(800);
+  ledcWriteTone(LEDC_CHANNEL, 3200);
+  delayMicroseconds(2000);
+  ledcWriteTone(LEDC_CHANNEL, 0);
+}
+
 void loop() {
 
     // Button pressed? (active low)
@@ -415,6 +432,9 @@ void loop() {
     if (digitalRead(KEY_4) == LOW) {
         Serial.println("Button detected: 4");
         button += 8;
+
+        atariKeyclick();
+
         digitalWrite(LED_USER, HIGH);    // Turn LED on
         delay(500);                      // Keep it on 0.5s
         digitalWrite(LED_USER, LOW);     // Turn LED off
@@ -422,6 +442,11 @@ void loop() {
     if (digitalRead(KEY_5) == LOW) {
         Serial.println("Button detected: 5");
         button += 16;
+
+        ledcWriteTone(LEDC_CHANNEL, 3200);
+        delay(8);
+        ledcWriteTone(LEDC_CHANNEL, 0);
+
         digitalWrite(LED_USER, HIGH);    // Turn LED on
         delay(500);                      // Keep it on 0.5s
         digitalWrite(LED_USER, LOW);     // Turn LED off
@@ -429,6 +454,11 @@ void loop() {
     if (digitalRead(KEY_6) == LOW) {
         Serial.println("Button detected: 6");
         button += 32;
+
+        ledcWriteTone(LEDC_CHANNEL, 3200);
+        delay(8);
+        ledcWriteTone(LEDC_CHANNEL, 0);
+
         digitalWrite(LED_USER, HIGH);    // Turn LED on
         delay(500);                      // Keep it on 0.5s
         digitalWrite(LED_USER, LOW);     // Turn LED off