Exchange Rate Difference Purchase Receipt and Invoice

Hi,
In the ledger of the Stock received but not billed, there are difference in values between the Purchase invoice and the Purchase Receipt when the item is in an other currency because of the posting time.

Is there a way to force the validation of the PR vs PI to be sure that the value are the same?

Normally I proceed this way:
I create the PO, PI and when I receive the items, I create the PR. But the PR total value is different that the PI because of the exchange rate and then the valuation of the item is not good.

Thanks

Does this setting in “Buying Settings” help?

The check box Maintain same rate throughout purchase cycle was already checked. Yes it works if I’m buying in the default currency but not if I’m buying in an other currency.

any ideas? Maybe I should write a script that validate the values??? I’m not sure how to do that.