Image size on fb wall after post k2 item

[vlachos]

Hi, after k2 item save, JV Social Publish post the item in fb wall but the image of item is small (picture 1).
What php file can edit so the component post large photo of k2 item (picture 2).
Both print screen is from same site but second image is from manual post (not component) link to fb wall.

Thanks for your time.