on-sale & category pages

Hello,

We have some filters setup and are having issues trying to get them to work. E.G the “on-sale”, when ticked shows all on-sales items, even when viewing a product archive for a category page.

I.E if we have

1. Category
   • Sub cat 1
   • Sub cat 2

The on-sale field when clicked, shows all store on-sale items instead of the ones just in any of the selected category.

This is when using the AND logic not OR.