Hello Miguel,
You may want to set your image quality in your easy social back end.
To do so you may want to go to your back end > settings > photos > uploader > set photo quality between the range of 60% to 80% as shown in this screenshot
http://screencast.com/t/z7AtiG8SfaMG . If the quality is above 80% it may result in larger image size.
Hope that helps
Regards
Kheng Wei