Was he using an IFB instead?
He has just switched to a tiny speaker hidden in his ear with someone else feeding him the speech. I am not sure why they did not do this long ago. It would be much easier for those times when they have to have his responses look impromptu. It actually would not suprise me if he had the thing shoved far enough up his ear canal so that camera’s couldn’t pick it up.
I once had a guy on my crew who snored loudly at night. It was uncomfortable using full size foam ear plugs, so I cut a couple way down. Unfortunately when I tried to pull one of them out it got pushed further up into my ear. My wife was able to get it out with tweasers, but she could hardly see it. I almost ended up going to the doctor.