A quick test of the screamer

pseudo-screamer.ino

#define SOUND_TRIGGER 9 // the pin attached to a trigger on the sound FX board

void setup() {
  Serial.begin(9600);
  
  pinMode(LED_BUILTIN, OUTPUT);

  // set up the pin for the sound trigger, including pulling it high
  pinMode(SOUND_TRIGGER, OUTPUT);
  digitalWrite(SOUND_TRIGGER, HIGH);
}

void loop() {
  Serial.println("Triggering sound!");
  digitalWrite(LED_BUILTIN, HIGH);
  trigger_sound();
  digitalWrite(LED_BUILTIN, LOW);
  delay(2000); // wait a couple of seconds
}

// fire off the sound
void trigger_sound() {
  Serial.println("trigger started");
  digitalWrite(SOUND_TRIGGER, LOW);
  delay(150); // you can try increasing or decreasing this length if the trigger does not fire
  digitalWrite(SOUND_TRIGGER, HIGH);
  Serial.println("trigger reset");
}