Weird, now that you say that; I detect a change with jutting jaw.
Slight pitch change upwards, not really louder.  How did you determine
the 14kHz?  I'm a software eng. It'd be interesting to get more data
from the millions of people with T.  Maybe there is an occupational
correlation to the types of T, who knows? Kids? You got it made!  You
said they prevent you from concentrating on or completing anything.
Isnt that the kind of distraction you're looking for?
My T is the high hiss as well. I seem to become aware of it more in the
evening, but also frequently during the day. I consider myself
fortunate compared to many of the people whose stories I've read here.
I've learned T can drive people crazy. It's like being in a constant
state of alert, having a siren in your ear for hours and days on end.
Your body wants to take flight, to get away. But there is no where to
go except to try to mask it with other noises. The result is mental
stress, physical fatigue. Vitamin supplements seem to help me, maybe by
replacing all the stuff the stress burns up. Daily Im taking 2gm fish
oil, 300mg CoQ10, 1gm calcium, 50mg manganese, 50mg B6, 1gm psyllium,
315mg green tea extract, 150mg saw palmetto berry extract, 25mg
diphenhydramine HCL; basically a meal of vitamins.  Keeping a journal
has helped a lot.  Reading back over it occasionaly and tying parts of
it together has helped reveal environmental factors that were affecting
the severity of my T.  For instance, I stopped drinking soda pop on
that basis. At any rate Y, if I figure out something that makes T
completely go away I'll be the first to spill the beans here... for
free! :-)

Hi again.  I'm an engineer too. My T is binaural and around 12KHz but it's a
compound tone, possibly something to do with the fact that the perception of
pitch of my two hearing channels doesn't track perfectly with frequency.
Mine cross over at 5.5KHz; below that one ear sounds slightly higher than
the other, above that the other one does...

Same here, though the tinnitus thus produced seems slightly 'different' as
if it's definitely coming from the two ears rather than any deeper.

My big tips are twofold:

1) Try taking ¼ aspirin a day long-term

2) Make up a little amplifier/hearing device that only amplifies around your
tinnitus frequency. This replaces the redundant tinnitus content with
information-bearing content, which the brain selects. The tinnitus gets
lost.   I am actually finding quite a market for some little devices that do
this. Newsgroup etiquette prevents me from saying more here but Google is
your friend.

Steve