Ionic 4 music - FF and Rewind

home.page.ts

  controlSeconds(action) {
    const step = 5;
    const numberRange = this.position;
    switch (action) {
      case 'back':
        this.position = numberRange < step ? 0.001 : numberRange - step;
        break;
      case 'forward':
        this.position = numberRange + step < this.duration ? numberRange + step : this.duration;
        break;
      default:
        break;
    }
  }