Older friend of mine uses a ReSound behind the ear hearing aid. These are equipped with a small volume up/down lever on the device itself, so he can tune the volume to match his environment.
Usually, this works perfectly, but if he is in call on the iPhone, pressing either volume up or down is intepreted as a press on the side button, meaning the call is dropped. He's been using hearing aids for 30+ years and thus tuning the volume is second nature to him.
Is there a way to stop this or change how the iPhone reacts to the button presses beyond contacting the developer of the hearing aid and asking them to push a new update?