I am using Coupons to give my dealers quantity discounts. I've set up two Product Types, 'headsets' and 'headset parts'. These two product types should be able to generate their respective discounts but when I place a discountable quantity of 'headsets' in after having already placed some discountable quantity of 'headset parts' items, the 'headset parts' revert back to the full price as if no discount at all were applied.
 
I saw one old April 2011 patch, but my software is 4.0.8, and that patch addressed a similar issue, not quite the same.
 
Any ideas?

Could you please send a ticket where describe what coupon code you are using, what products you're adding to cart and what is the desired effect you would like?
 
It's hard to advise anything from this description.
 
Thanks,
ViArt Team