Quantity discount is applied when Qty Min/Unit Mix: OFF

We have a product that has quantity discounts and a text input option with one time charge.

When two instances of this product is added to cart with different text input options they appear separately in the cart as expected, however the second product gets quantity discount based on the fact that sum of both product quantities hit next quantity discount level. How do we prevent that?

e.g. this is how it shows up in shopping cart:
Qty: 250 of Product X Text Attribute: "text input string A" Unit: $1 Total: $250
Qty: 250 of Product X Text Attribute: "text input string B" Unit: $.80 Total: $200

Instead we expect both instances of the product to have Unit: $1 Total: $250

Thanks.

Figured out.
Discount Qty Applies to Mixed Attributes: No