As said in the “Missing features & problems” topic, we’ve got some problems with ALSA multichannel soundcards: When running ALSA on soundcards with more than one output stereo pair, all channels except the first stereo pair will to be silent (at least in our test setups). The same setup worked with JACK.
Has someone with a working multi IO setup experienced the same problem or does it work? I can not test this right now here.
To test this in Renoise, you can simply go to the mixer and route a tracks output to a hardware channel that is NOT the main output. This can be done via the small track routing box at the bottom of the channel strips.