Base currency discrepancy between Billing and Receivables

On :  9.1 version, Currency

ACTUAL BEHAVIOR  
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Base currency discrepancy between Billing and Receivables  
A Foreign Currency Invoice with Full Payment in AR results in base amount discrepancy between Billing and Receivables.

EXPECTED BEHAVIOR
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No discrepancy between Billing and Receivables  for invoices/payments

STEPS
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The issue can be reproduced at will with the following steps:

1) Set Exchange Rate GBP to USD =1.5838
2) Enter Invoice with 13 lines in Billing module, Currency is GBP with a Base Currency of USD
3) Finalize invoice and send it to AR as a pending item
4) Post pending item in AR
5) Apply Payment in AR module for full amount of invoice