playLooped method
Starts sound with looping.
delay - delay before sound will be played again. Clamped positive.
Implementation
void playLooped({Duration delay = Duration.zero}) {
  super.stop();
  final delayMs = delay < Duration.zero ? 0 : delay.inMilliseconds;
  if (!_sound.looping.$1 || _sound.looping.$2 != delayMs) {
    _sound.looping = (true, delayMs);
  }
  super.resume();
}