int threshold = 523; //set to value read when device is used //was 523
int bootdelay = 5000; //set to ms delay after boot
int duration = 2000; //set to desired mute duration

int sensorgnd = A3;
int sensorvcc = A4;
int sensor = A5;
int relay = 11;
//int relay = LED_BUILTIN; //for testing purposes
bool mute = false;
int value;
unsigned long timer;
unsigned long snapshot;

void setup() {
  // initialize the digital pin as an output.
  pinMode(sensorgnd, OUTPUT);
  pinMode(sensorvcc, OUTPUT);
  pinMode(sensor, INPUT);
  pinMode(relay, OUTPUT);
  digitalWrite(sensorgnd, LOW);
  digitalWrite(sensorvcc, HIGH);
  digitalWrite(relay, LOW);
  delay(bootdelay);
  Serial.begin(9600);
}

void loop() {
  timer = millis();
  value = analogRead(sensor);
  Serial.println(value);
  if (value >= threshold){
    snapshot = timer;
    if (mute == false){
      mute = true;
      digitalWrite(relay, HIGH);
    }
  }
  else if (value < threshold){
    if (mute == true && timer - snapshot >= duration){
      mute = false;
      digitalWrite(relay, LOW);
    }
  }
}