I used to do a lot of interviewing of prospective hires at my last job (I'm a programmer). It was not at all uncommon to ask a candidate a question and then hear multiple voices whispering in the background along with frantic keyboard tapping sounds, and the candidate would take 5-10 seconds before answering. I just don't understand what their thought process was for even attempting this - it earned them an immediate "no further action".
I won't say what country all of these candidates were from. It would be obvious to anyone in this field.