F110 Grouping of open items in proposal

Hi

Our customer invoice creation triggers from external system which posts the document through bapi. Problem is for each material, system is posting one open item per invoice. As a result, if in one invoice there are 10 material, then under one FI document, system is posting 10 open items with posting key 01.

The impact is coming in F110 run. It is taking a good 7 hours to process the entire list of customers, I can see for each customer , when I go inside the proposal, 10 items with same fi document numbers are appearing. is there a way to consolidate this ? F110 is by default grouping the customer, but inside the customer, can i also group the invoices which have the same document number /reference number ?

Br....Subha