const int buzzerPin =  A2;

int buzzerState = LOW;             // ledState used to set the LED

unsigned long previousMillis_1 = 0;        // will store last time LED was updated
unsigned long previousMillis_2 = 0;        // will store last time LED was updated

const long interval_1 = 337;           // ON time
const long interval_2 = 1000 - 337;          // OFF time

void setup() {
  pinMode(buzzerPin, OUTPUT);
  digitalWrite(buzzerPin, LOW);
}

void loop() {

// here is where you'd put code that needs to be running all the time.

//

// and this checks if it is time to change the buzzer
  unsigned long currentMillis = millis();

  if (buzzerState == HIGH) {
    if (currentMillis - previousMillis_1 >= interval_1) {
      digitalWrite(buzzerPin, LOW);
      previousMillis_2 = currentMillis;
      buzzerState = LOW;
    }
  }
  else { // buzzerState == LOW
    if (currentMillis - previousMillis_2 >= interval_2) {
      digitalWrite(buzzerPin, HIGH);
      previousMillis_1 = currentMillis;
      buzzerState = HIGH;
    }
  }
}