We have a problem with tax/VAT settings on our 220.127.116.11 Magento store.
When we change the billing address in the checkout, the order lines and totals change, but incorrectly.
We have set different tax rates for the countries we ship to, for example 6% for Netherlands and 10% Austria. For every country (14) there is a separate storeview.
We have a product that costs €59,00, and when we add this to the cart in the Austrian store, the total without tax is €53,64 and with tax is €59,00. This is correct.
However, when we change the billing address to Netherlands, there is tax calculated, but based on the previous amount without tax, so €53,63 without tax and €56,85 with tax. The last one should be €59,00, this is the problem.
I can see how the NL totals are calculated on the Austrian storeview:
53.64 / 100 * 110 = 59 (Austria, correct)
53.64 / 100 * 106 = 56.85 (Netherlands, incorrect)
This last one should be 59, so the amount with tax should be leading, now the amount without is used for recalculating.
If I do the same on the NL storeview (change billing country to Austria), the opposite occurs:
55.66 / 100 * 106 = 59 (Netherlands, correct)
55.66 / 100 * 110 = 61.23 (Austria, incorrect)
I hope I'm clear enough..
How can I solve this?