So you know how some people tilt their phone sideways when they talk into it? Like some sort of walkie-talkie.
Why do people do that? I mean seriously, how much difference does that miniscule reduction in distance between mouth to mircrophone make? None! If they can’t hear you when you speak in the first place, then just speak up, or move to a place that gets bettere reception, change your phone or ask them to do the same.