Well Hello, to another 'rare' one! The deepest part of my 'cookie bite' is at the sound of human voice, so I understand the restaurant and backseat talkers problem.
The explanation I have been given is restaurants and cars are high in 'distraction noise'. In a restaurant I try to sit in a corner against the walls. I have removed the one hearing aid that was facing away from my party.
In a car, I put my head between the seats, with no radio and no open windows.
I have been told there is no technology that will fix these problems.. yet. In a restaurant, my best bet is lip reading.
I tried (Biocore?) with controls on the phone to focus the 'hearing area" more towards the front centre or the sides... but you could not work the aids independently, other than turning it off. I did not find this useful.. just fancy.
With my now profound loss at human speech, I am to hone my lip reading skills.
It is a sorrow to realize this cookie bite will advance. We can hope that the technologies will continue to advance for us, and without delay.
Please let us know if you discover any new advances.
All the best.