Bug in GraphicRiver

Some items in graphicriver are showing a black shade in the preview…its a bug in graphicriver! please fix it!

cheak : http://graphicriver.net/item/corporate-business-card-bundle/13001967
http://graphicriver.net/item/corporate-trifold-brochure/13004082
http://graphicriver.net/item/corporate-trifold-brochure/13004082

There is a problem only with new items.
One of my items was approved yesterday and I had to reupload all the images again.
There is no other fix, in my opinion, as the images have been changed, it’s not just a filter or something.