Solution : https://service.sap.com/sap/support/notes/135103 (SAP Service marketplace login required)
Key words :
system rounds values slightly differently, additional key words rounding, smallest currency unit, scheduling agreement item, correctly debited gbp 1, local currency determined, respective incoming invoice, purchase order item, 20 pcs dem 156 / pc = 3, exchange rate difference
Related Notes :
518114 | FAQ: Goods movements in foreign currency |