Hearing protection.

33IMP said
As a tinnitus sufferer, I find I have to have noise, a TV, radio, Dvd on to be able to sleep. If the noise stops, I immediately wake up.
But I do find it is a fine excuse to ignore the girlfriend when she won't shut up.

I'm really fortunate, was around lots of aircraft. My hearing is mostly intact, except for the frequency that allows me to hear my wife.