https://pmc.ncbi.nlm.nih.gov/articles/PMC3746176/
So here it could indeed just fire off speech and you know what? We'd probably convince ourselves that we absolutely meant to do that. In fact it could be a very interesting experiment (with willing participants). Mess with the inputs the device receives so it's not really the person activating it, let it do it's thing and see if they notice when they do/don't have control of it.