Yes I understand your thought Ralph, possible even that it is not fully functional on Linux, only that it is strange because the channels on the mixer seem to be there to do it. In any case, it is possible that with the current HDSPMixer, it can only work with outputs 3 and 4, I am investigating further by asking also in the RME official forum. In any case, that's fine with me because my aim was to have an additional stereo output, completely independent of the HDSPe AIO and I did it. I just wanted to understand if the other 2 could be used as well. Thanks _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user