If you're doing your own sampling, sooner or later you'll come across a sample that will be out-of-tune with the samples around it. You might even have a group of samples, each of which may be out-of-tune. This tuning problem can be fixed within Kontakt 2's Mapping Editor, which has a Tune function where a sample can be fine-tuned. While the Tune feature allows you to retune by up to 36 semitones up or down, most often you will be using fractional amounts, such as +0.18 or -0.22. If all the samples are sharp or flat by the same amount, then you should use Kontakt 2's Global Tune knob to bring all the samples up or down to proper pitch, which is usually A=440. This virtual "tune knob" can be found just to the right of the sample program's name.