Title not hidden on page

I'm using the Corporateclean theme, and the node titles just refuse to be hidden by exclude node title.
This is what the code is to print the title in page.tpl.php Is it interfering somehow?

<?php print render($title_prefix); ?>
            <?php if ($title): ?>
            <h1><?php print $title ?></h1>
            <?php endif; ?>
            <?php print render($title_suffix); ?>

            <?php if ($tabs): ?><?php print render($tabs); ?><?php endif; ?>