my hum started in ernest about two years ago, I noticed that the frequencies
of the white noise of the surf (i.e the high, static-y noises) plus the gray
noise of the surf (the low rumbles as the waves drag against the shore)
effectively cancel out the hum for me. I think especially the low frequencies,
which makes sense since the hum is a low frequency, but also the higher white
noises add a type of distracting signal for me.
Just a quick note :
You find that the sound of the surf, then the drag against the shore help
you sleep :
I am exactly the opposite !
I tried one of those waves-on-the-shore C.D.'s, and although it's
nice, if I'm trying to get to sleep, I keep
noticing each time the wave comes in, then I'm waiting for the rush
back down the beach/shingle, then I'm waiting for the next wave, and so on
! I find a 'dead-steady' sound is best for me,
as with the 'sound conditioner' , or 'noise masker' machines : they
make a very steady 'hiss' sound, which
you accept more readily I suspect than a fluctuating sound. Even though the
sound they make is fairly high-pitched, it distracts the attention a
little.....and at least it gives the feeling that you're putting something of
YOUR choice between you and the nuisance from outside.
As you say, different folks react differently,
but so glad your C.D. helps you anyway.