After some more tries, starting the "for each loop" and ending it with "unswizzle" inside the DLT seemed to have fixed our problem. 

Thank you all for the replies 

Hello,

Thank you for the reply. However i don't see this working for this case. We already have an element in the BPL that uses a recordmap to make records out of the CSV to send them to the DTL. We can only get the csv by a REST call, so using the BusinessServer for record maps is not realy an option. If the best way to do this is without a record map we would also like to know.