Not working on front end with tax_query

I noticed the order is not menu order when using a taxonony query. Example:

$args = array(
    'posts_per_page' => -1,
    'post_type' => 'portfolio',
    'tax_query' => array(
        array(
            'taxonomy' => 'portfolio_cat',
            'field' => 'id',
            'terms' => array(5)
        )
    ),
);

$posts = get_posts($args);

I’m not sure if this is the best solution, but i ended up adding this to my functions.php to fix it:

add_filter( 'pre_get_posts', function( &$q ) {
	$order = '';
	if (isset($q->query['orderby'])) {
		$order = $q->query['orderby']; 
	}

	if (false === strpos( $order, 'menu_order' )) {
		$q->set( 'orderby', 'menu_order' );
		$q->set( 'order', 'ASC' );
	}
});

I feel this should be fixed within the plugin itself.