The last page of my marketpress productlist is showing the wrong products

I am using the short code for product list [mp_list_products paginate="true" page="1" per_page="16"] on my site and this was always working good.
On this moment I have 14 pages showing my products.

I don't know when it exactly happened but one of my customers told me that the products on the first and the last page are the same. I can not find anything what I did wrong.
Take a look at page 1: http://ellad2.com and page 14 http://ellad2.com/beading-tutorials-page-14/