Duplicate posts in loop.php

Im trying to grab posts in the loop by post_type. I only want to display 4 posts. But 24 posts appear.

Any ideas?

Here is my code:

<?php elseif ( is_home() ) : ?>
                <?php $my_query = new WP_Query( array( 'post_type' => 'portfolio', 'posts_per_page' => 4, 'order' => 'ASC', 'cat' => 8) ); ?>
                <?php while ($my_query->have_posts()) : $my_query->the_post(); ?>
                <div class="other-works">
		<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
                    <div class="title-bg">
                        <h2 class="entry-title">
                            <a href="<?php the_permalink(); ?>" title="<?php printf( esc_attr__( 'Permalink to %s', 'twentyten' ), the_title_attribute( 'echo=0' ) ); ?>" rel="bookmark"><?php the_title(); ?> > </a>
                        </h2>
                    </div>
                        <div class="post-thumb">
                            <a href="<?php the_permalink(); ?>" title="<?php printf( esc_attr__( 'Permalink to %s', 'twentyten' ), the_title_attribute( 'echo=0' ) ); ?>" rel="bookmark"><?php the_post_thumbnail();?></a>
                        </div>
                </div>
                </div>
                <?php endwhile; ?>
        <?php else: ?>