Parent nodes with wrong totals

Dear experts

We are facing some issues with parent nodes of the dimension ACCOUNT. I'll try to explain without screenshoots; the hierarchy looks like this:

Node A (parent)

---Node B (child)

---Node C (child)

With amounts:

Node A (unexpanded) --> $80

If I expand the Node A to see their childs, the result is:

Node A (expanded) --> $120 (not $80!!)

   Node B --> $100

   Node C --> $20

We have EPM 10 SP 19 patch 1, .net 4. Any ideas to solve this issue?

Thanks in advance. Regards,

Manuel