Correct payment but wrong Currency in Payment Record / Invoice

I’m using WooCommercy Multi Currency now since a couple of days in a way, that people can choose their currency on the product pages, but checkout needs to happen in Euro.

This mostly works, but in some cases I get a wrong currency in the orders.

For example (see screenshots), people have ordered something for 99€ – the order instead shows 99 US$ and the wrong € amount, but the charging via paypal was 99€ (correct).

Unfortunately the wrong currency in the order record also appears in the invoice and my statistics.
This looks like a major bug to me.

You can find my configuration in the “config.zip” file attached.