Currency rounding mismatch between checkout and payment amount

[sandomatyas]

Hi

I might be misunderstanding something in the configuration, so I'd like to ask.

I'm using two currencies, where one is the default, and the second one is calculated from it via exchange rate. Both are set to 0 decimal places. I also tried switching the "Round only display" setting on and off.

Example:

Product price in default currency: 500
After currency switch, the calculated value is not an integer, but since decimals are set to 0, it is shown as €1 in the frontend (rounded)
But during checkout/payment, the amount becomes €1.33

Because of this, the price shown on the site and in the checkout differs from the amount shown by the payment provider (e.g. PayPal).

What would be the correct way to handle this?
How can I make sure the payment amount matches what is shown in the checkout?

Thanks!