project for digispark with Atmel ATTiny85, makes random noise, every pin (0-5) have to be conected with speaker or piezo

randomNoiseTones.ino

int randomSound, delayPeriod;

void setup() {
}

void loop() {
  delayPeriod=random(1,10);
  for(int pin=0;pin<6;pin++){
    randomSound=random(20,1000);
    noTone(pin);
    tone(pin, randomSound, delayPeriod);
  }
  delay(delayPeriod);
}