i think in some cases it may be a physical issue, but there also seems to be a distinct difference between hearing
tones and full or partial hearing
loss.
sandra described both actually, if i'm not mistaken. i was responding to the part about hearing tones. the issue with background noise interfering may be a genetic thing, i don't know. but i don't think hearing tones is automatically indicative of a problem.*
i am not a doctor! if you are concerned about your hearing, please see one.