Issues creating custom Flexslider navigational arrows

I am using Flexslider v2.0 and am trying to create my own custom navigational arrow that will sit directly below the slideshow.

From what I have been reading I have to create my own slider navigation and make use of the Flexslider "controlsContainer" & "manualControls" controls.

So far I have only achieved making the new custom arrows navigate only 1 step forward or one step backwards. I cannnot get it to navigate like the built in navigation arrows.

Here is the code:

CSS

.flex-direction-nav2 {  }
.flex-direction-nav2 a {width:30px; height:30px; margin:-20px 0 0; display:block; background:url(../images/flexslider/bg_direction_nav.png) no-repeat 0 0; z-index:10; cursor:pointer; text-indent:-9999px; -webkit-transition:all .3s ease }
.flex-direction-nav2 .flex-next {  display:inline-block;background:url(../images/shortcodes/testimonials/arrow-right-01.png) no-repeat 50%; background-color:#000; right:-1px; z-index:6}
.flex-direction-nav2 .flex-prev {  display:inline-block;background:url(../images/shortcodes/testimonials/arrow-left-01.png) no-repeat 50%; background-color:#fff; right:25px; -webkit-box-shadow:3px 0 0 0 #fff; box-shadow:3px 0 0 0px #fff; z-index:5}

HTML

<div class="testimonial-container clearfix">
  <div class="title">
    <h3><span>What Client’s Say</span></h3>
  </div>
  <div class="testimonials clearfix">
    <ul class="slides">
      <li>
        <div class="testimonials-content">CONTENT</div>
      </li>
      <li>
        <div class="testimonials-content">CONTENT</div>
      </li>
      <li>
        <div class="testimonials-content">CONTENT</div>
      </li>
    </ul>
  </div>
  <ul class="flex-direction-nav2">
    <li><a href="#" class="flex-prev">Prev</a></li>
    <li><a href="#" class="flex-next">Next</a></li>
  </ul>
</div>

jQuery

/* Testimonial Slider */
$('.testimonials').flexslider({
    animation: "slide",
    directionNav: true,
    controlNav: true,
    animationLoop: true,
    pauseOnAction: true,
    pauseOnHover: true,
    nextText: "Next",
    prevText: "Previous",
    controlsContainer: ".testimonial-container",
    manualControls: ".flex-direction-nav2 li a"
});

Any help would be greatly appreciated.

Thanks