I have just been fitted with a zest spirit p hearing aid and noticed that on the back is a silver toggle switch. The audio guy did not mention this switch when he fitted it. I assumed it was some kind of volume control but it does
nt appear to make any difference when I press it either one way or the other. I wear two aids and the other one is an Oticon spirit with just a small button for using the loop system I think. I needed the new aid which he told me was a bit more powerful, the other ear seems to be OK. Being blind I didnt notice this little toggle at the time and there was no instruction leaflet with it. Can someone tell me its purpose please.