I suffer from tinnitus. Most of the time it is a minor irritant, but loud noises, especially higher pitched ones, can aggravate it to the point where it actually becomes painful - for example the loud squealing of train brakes I hear at Reading station. I find the repetition of announcements annoying but at least they don't normally trigger bad tinnitus, unless they are exceptionally loud, as was the case today in the middle carriage of a 166 on the North Downs line where the loudspeaker was set to a much louder volume than normal. In contrast, the speakers at my local station (Sandhurst) are so quiet I can barely hear them, even when stood directly underneath.