Pictures not loading anymore (404 error)

Hi there,
This morning I add to change one setting on my CDN provider to Allow Cross Origin Resource Sharing.
Since then, images are sending a 404 request. The minute I deactivated the a3 plugin, everything was loading fine again.
Here is a screenshot of my console with a3 activated : https://www.dropbox.com/s/jymq3wultt58gvc/Le%20meilleur%20kart%20%C3%A0%20p%C3%A9dales%20en%202018%20-%20Comparatif%2C%20guide%20et%20avis%20-%20Google%20Chrome.jpg?dl=0

Is there any plugin cache that I have to empty maybe?

Thanks

Julien