Unable to control multiple RME Fireface UC soundcards with ASIO

[bdieudonne]

When trying to launch an experiment with driver ASIO, while two RME Fireface UC soundcards are connected to the computer (and visible for the computer), Apex gives the following Error:

Soundcard: unspecified error

additional soundcard info: Failed to start ASIO streaming

Some extracts from the log in cmd:

apex: Card name: ASIO Fireface USB, Driver name: asio
[...]
apex.streamapp: max channels: 36
[...]
Starting ASIO test...

So Apex appears to find the soundcard (the name of the soundcard was not given in the experiment file), knows the amount of available channels (this was also not specified in the experiment file) but errors when ASIO test is started.

Error can be reproduced by launching any experiment in Apex with driver set to asio in the devices, and launching the experiment (on Windows) while two RME Fireface UC soundcards are connected.