Have you noticed that if you listen carefully to a news program like Today on BBC Radio 4, you can hear a keyboard being typed in the background. I find this infuriatingly distracting, especially when it is quiet first thing in the morning. I enquired of a computer tech friend at the Beeb a while ago if they suggest a silent keyboard for use on air because we wanted one for use in church but he said that they had no particular recommendations and just used whatever came. I was surprised considering the effort they put into the acoustics of other equipment in the studios and I would have thought they would specify a membrane device even though they are much slower to use. Alternatively I would suggest an under-desk keyboard shelf (perhaps with a clear window for non-touch-typists) to screen the noise from the microphone.