So, in short, if I walk up and press a button, I have no indication whether that button will give me an audible signal... Probably for that reason, the audible

So, in short, if I walk up and press a button, I have no indication whether that button will give me an audible signal... Probably for that reason, the audible signals around here are audible all the time - there's a slow tempo signal for "stop" and a significantly more urgent, higher tempo signal for "go".