I don’t think the error is in the Export function – or if it is, it’s the same code used by Reports.
We have basically the same issue with 7.11.7:
In a contact-based table (“Candidates”), we added a field for Currency_id, along with several Currency type fields to hold salary/rate information for that candidate.

In the Candidate record, all looks and functions just fine – the data is saved as entered each time:

Similarly, in the list view the currency is correct for each candidate, regardless of currency selected:

However, the first incorrect currency amount occurs on doing a simple report:

On going back to the individual Candidate record or to the Candidates list view – everything remains correct there, yet the Report currencies are not right.
Further, when exporting, the amount remains with the wrong currency symbol, as well as exporting an odd string for the currency_id field:

The correct export would reflect what is seen both in the List view and the individual record view, and should look as follows:

But, it is not so (I edited the above to show what it should look like).
I’m at a loss to explain this – for now, we may need to do reports by printing from the List view … or manually checking all our exported/reported figures. It’s a bit tiresome!
Any help would be very much appreciated. Not adverse to a bit of php tinkering :whistle:
Thanks!
Dave