Price in shipping calculator stay the same even if the currency changes.

A client notified me that he was struggling with US$ checkout. On inspection I saw that the price in ZAR is correct, but when you change the currency to US$ the price stays the same…just the R changes to $. I have not had this problem before. It is also only with international shipping when using Aramex. It works well with weight based domestic shipping.
Domestic is in South Africa and the rest of the world as international shipping.