I think it possible if anyone cares to go to the trouble ,
I know of execs that change cell phone numbers every couple of days, its easy to tap into them and turn them on....
I would like to hear what major companies use now,
I know there are many ex-KGB type people in Europe that can get into anything electronic and tap anything ,
If its important then spend the money for a pro to sweep the room and maybe play "white noise" to screw with the recording devises.
I have even heard of people putting up ez-up canopies in their rooms to stop spy cameras embedded in the ceiling etc.
Rally