I have a Specialized Hardrock 2011 Disc brake mountain bike with a front brake that squeals when used lightly. It's OK if I use the brake hard - but I usually don't need or want to stop in such a hurry! I have been using the rear brake more for light braking, which is something that I don't like to do because the front brake is best for this.
It has been like this pretty much since the day I got it, so I initially put it down to needing running in. It has got a bit better with time and a few hundred miles, but not much - I try not to brake and instead carry the momentum of the bike where I can for increased efficiency.
What should I look into adjusting to stop disks squealing?