The FAA medical has got to be the easiest in the world, and they don't really care. But I've applied for some overseas airlines, and saw eyebrows raised when they looked at my audiology test results. Is it even worth trying at KAL?
GoForIt
They do have an audiology test. I'm not sure how strict they are, but I have seen captains with hearing aids.
If it helps: You sit in a both, headset on, clicker in hand. Three tones (beep beep beep) of one freq are played at random intervals and decreasing volume. Click after each set of three. They check five frequencies. First left ear, then right.