Smush does not smush 300x224 Wordpress generated images

Hi,

This website has been smushed. http://cleverworks.com.au

However the page load speed is still 8.72s

The GTMETRIX report here http://gtmetrix.com/reports/cleverworks.com.au/7cfifuGg

Says that Smush did not decrease the file size of wordpress generated thumbnails.

Also, the front page of Cleverworks is running a Marketpress products shortcode.

Are the page load speed issues caused by Marketpress or WP Smush Pro?

Any ideas?

Cheers,

Johnny