An example of such a question that would not be suitable on music.stackexchange.com or sound.stackexchange.com is basically anything to do with the linux workflow on audio production, e.g. problems with setting up the Jack Audio Connection Kit, typical / recommended linux setups, conversions to LADSPA plugins, enabling communication between PulseAudio and other sound engines, how to apply a particular effect on Audacity, how to re-route MIDI input from a keyboard to a particular piece of software, etc.
I disagree with the point that this is within the scope of music.stackexchange.com based on the answer to "what can I ask here" in the help topic including "usage of specific music software or hardware", as this is presumably linked to the points above it, i.e. software or hardware relevant specifically to:
- practice or performance technique
- music theory, notation, history, or composition
- technical analysis of a specific, complete work, or well defined section thereof
- instrument maintenance or repair
Similarly, as Jacques already pointed out in his answer, sound.stackexchange.com is also not a suitable place to ask this, as that seems to deal more with (taken from the "what can I ask here" help topic:)
- sound design in the film and video game industries
- live production audio
- mixing and recording in a studio from the perspective of the sound tech
i.e. dealing with consoles, professional studio setups and sound equipment, best recording practices in the industry, etc.
I also disagree with topo morto's comment about music.stackexchange.com being a suitable place to discuss production just because tags like "cubase" exist. I would say that such tags exist purely as a case of that forum being the lowest common demonimator for the time being, but this still doesn't mean that it is the best place for such questions, nor that it will attract the kind of community that deals with such questions.