Randomize posts using globalpost

I’m trying to randomize the appearance of posts and their thumbnails on my homepage by adding orderby=rand in my category.php file. I’m using a child theme of Dessign’s Style theme. For some reason the orderby=rand array tag is not working and I don’t understand why.

I’m developing locally so cannot post a link.

Any help would be greatly appreciated. Thanks!

Here is the relevant snippet of code:

<?php
     global $post;
     $myposts = get_posts( 'orderby=rand&numberposts=7&category_name=Featured Small' );
     foreach($myposts as $post) :
       setup_postdata($post);
     ?>

      <div class="small_box">
      <h3 class="bottom_line_title"><a href="<?php the_permalink(); ?>"><?php echo substr(get_the_title(),0,20); ?><?php if(strlen(get_the_title() > 20)) { ?>..<?php } ?></a></h3>
      <?php
      if ( has_post_thumbnail() ) {
        ?> <a href="<?php the_permalink(); ?>"><?php the_post_thumbnail('featured-small'); ?></a> <?php
      } else {
        ?> <a href="<?php the_permalink(); ?>"><img src="<?php echo catch_that_image() ?>" /></a> <?php
      }
      ?>
      </div><!--//small_box-->

    <?php endforeach; ?>