Wordpress not sorting by custom field when tax_query is active on custom taxonomy

Question

I have to sort the products by price. I'm srugling with this task, because my query works only when any custom taxonomy querying is off. This is query that works, yet it doesn't filter posts by a specific product_category:

$args = array(
    'post_type' => 'product',
    'paged'     => $paged,
    'orderby'   => 'meta_value_num',
    'meta_key'  => 'price',
    'order'     => 'DESC',
);

Now this code:

$args = array(
    'post_type'  => 'product',
    'paged'      => $paged,
    'orderby'    => 'meta_value_num',
    'meta_key'   => 'price',
    'order'      => 'DESC',
    'tax_query'  => array(
        array(
            'taxonomy' => 'product_category',
            'field'    => 'slug',
            'terms'    => $queried_slug
        )
    )
);

It queries the correct category, but doesn't do the sorting at all. I'm not sure how this is even possible.

This is the environment:
Wordpress: 4.4.2
Custom fields management with "Advanced Custom Fields"
Custom post types and taxonomies with "Types"

Here's the SQL that's generated:

SELECT SQL_CALC_FOUND_ROWS  wp_posts.ID FROM wp_posts
LEFT JOIN wp_term_relationships ON (wp_posts.ID = wp_term_relationships.object_id)
INNER JOIN wp_postmeta ON ( wp_posts.ID = wp_postmeta.post_id )
LEFT JOIN wp_postmeta sort ON (wp_posts.ID = sort.post_id AND sort.meta_key = 'sort_487')
WHERE 1=1
AND ( 
  wp_term_relationships.term_taxonomy_id IN (487)
)
AND ( 
  wp_postmeta.meta_key = 'price'
)
AND wp_posts.post_type = 'product'
AND (wp_posts.post_status = 'publish' OR wp_posts.post_status = 'acf-disabled' OR wp_posts.post_status = 'private')
AND ( sort.meta_key = 'sort_487' OR sort.post_id IS NULL )
GROUP BY wp_posts.ID
ORDER BY CAST(sort.meta_value AS SIGNED), wp_posts.post_date DESC LIMIT 0, 18