If you apply entries in different currencies, you must set up the G/L account to which you want to post rounding differences.
Open the Customer Posting Groups window.
In the Debit Curr. Appln. Rndg. Acc. and Credit Curr. Appln. Rndg. Acc. fields, enter the relevant G/L account number.
Allowing for Rounding Differences when Applying Customer Ledger Entries
Allowing for Application of Customer Ledger Entries in Different Currencies