progress(val) {
    if (isNumber(val)) {
      if (val < 0 || val > 1) {
        const clamped = clamp(val, 0, 1);

        this._warning(WARNING.PROGRESS_CLAMPED(val, clamped));
        this._setProgress(clamped);
      } else {
        this._setProgress(val);
      }
    } else {
      this._warning(WARNING.PROGRESS(val));
    }

    return this.config.progress;
  }
delay
Responsible for setting playback progress.
@public