Display Product Price/Add to Cart

We are having and issue when customer try to add multiple products to the shopping cart, if you click the link below and try to add products to the cart it says "Your shopping cart is empty".

We are using SEO URL and running zencart v1.3.9d, any help would be greatly appreciated.

Example

I did disable the option under configuration>product layout>Display Product Price/Add to Cart, but we would like to use this feature.

Thanks

If you turn off the SEO/rewrites does it work correctly?

I totally disabled seo url and it does that same thing.

Try disabling the SEO/rewrites and switch to the Classic Template and see if it works ...

NOTE: be sure to navigate to a Category without the rewrites being active when you test ...

I restored the original htaccess (rewrite off) prior to installing SEO URLs, disabled SEO URLs under configuration and tested with a theme that hasn't been modified and we are still seeing the "Your cart is empty" message. Thanks for the ideas, any others would greatly appreciated.