WPSmush and Amazon S3

Hi guys,

I seem to be having an issue with my images being smushed. It continually displays "Smushing in progress"

I have a setup with WP Offload S3 that sends my images through to the amazon servers upon upload. I have looked through the forums and found a 'solution' where you add the following define('WP_SMUSH_ASYNC', false); to the wp-config file but it does not seem to have made a difference.

Any ideas?