Maybe it's still set to the audiogram that was taken. Hearing loss is only so when it is greater than 20 dB so even if the audiogram is mostly 5-10 dB it can still be set to that.
Maybe you had hearing loss in higher frequencies. I assume the hearing tests you had only went up to 8 kHz?
So glad it worked for you though :)
May I ask your age?
So when this thing rolls out and it successfully treats most of us, is it the kind of thing that will be presented on BBC News etc? Basically a huge media spotlight?