Ax2012R3CU8 - co-product cost allocation

Something strange happen:

In my Production (my customer) they will often produce something not identical With the Production setup. They intend to produce Product A, configuration A, ut result is Product A, configuration B.

Using TCA

Alle Inventory transactions are correct updated, but the cost alocation result is wrong. All material consumption are calculated to 50%, and then correctly Distributed. Even the produced coproduct are (example) units, and inventtrans show consumption of 80 units, the 100 produced units will have 50% of the material cost.

WHY? what is wrong?