The only thing that is a little sad about it is that for example the faders do nothing when the R16 is in USB audio interface mode.
It does however like to randomly turn on reverb and one other effect after power cycling. Which I sometimes forget and then wonder for half a second why the audio is sounding weird :P So there is some extra functionality that is available even in USB audio interface mode, although in this case not desirable for me to have enabled within it. If I want to add reverb or other effects when using the R16 as USB audio interface, I prefer to do so in the DAW. I would have liked to be able to use the faders though.
