Solution : https://service.sap.com/sap/support/notes/544794 (SAP Service marketplace login required)
Key words : 
prerequisites program error solution, rounding differences occur, tax base amount, /3 frontend message quoting, item        gross     net, gross amount reason, 75              16the correct net, gross invoice, correct total, symptom 1tte
Related Notes : 
       
| 540465 | Rounding for taxes wrong if statistical items exist | 
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