Paramedic Christian Hill, 48, is telling me about suffering from what audiologists call “cocktail party syndrome”. “I could hear background noise but I couldn’t pick up on any particular conversation. Looking back there were lots of clues. I’d have to ask people to repeat things. Someone once said: ‘Why are you just looking at my mouth?’ I would have to lip-read a little bit to give me that visual cue for what they were saying. It got worse and worse, to the point where if I was in a noisy envir