I have been having this problem this year with Pepsi, Coca Cola, Schweppes, Sprite, and one can of Chang Beer.
On all occasions, small "pinholes" appear in the base of the cans and the product usually leaks and evaporates, and sometimes leaves a messy residue I have couriered all the empty cans, with a typed letter back to each company and all have responded with explanations and replacement product.