Very annoying indeed... I remember as a child I would constantly be exposed to the 15.7K whine of old TVs, but now every time I hear one of those, I have a love hate relationship with that sound and it drives me insane. I've also heard this type of sound with squeaking breaks (up to 18K sometimes) and I want to pull my head off and throw it because it is so piercing LOL. I'm 20 and can still hear up to 20 K, though it is quite faint... most people I am at college with can barely hear 18K and complain of Tinitis and blame it all on the fact that they are musicians. Hmm, it'll be interesting to see how well I can hear as I age, but I do plan on getting the best out of every frequency range I have while I have it LOL.