Min/Unit Mix not working for products priced by attributes

[kgmmusic]

I just noticed a problem on a LIVE store and hope someone here can point me in the right direction.

I have several products setup as "priced by attributes" allowing the customer to choose BLANK or PRINTED along with quantity discounts. I turned the Product Qty Min/Unit Mix ON but the quantities are not being combined at checkout. The sample item has a 150pc minimum so I thought that if I added 75 WHITE and 75 LT BLUE that it would combine and display the 150 QTY price of $2.70 each, however that is not happening and instead it is displaying $0.00 for both items.

I suspect this has something to do with the way I have the product set up using "priced by attributes" and the fact that 1-149 QTY displays $0.00 in the popup. I tested another product that has a more basic pricing and it is working as designed so it appears at this point that only the products that use "priced by attributes" are being effected.

Please have a look at the example below and let me know if I am doing something wrong. THANK YOU!

SAMPLE URL: http://www.bestpriceuniforms.com/ind...roducts_id=429