I can't (correctly) modify the root note of a sample in FLS12?

Perhaps there's some incredibly obvious step I'm missing here because I'm new to everything, but according to every resource I can find, all I need to do to modify the root note of a sample is to right-click the note that I want the root to be in the envelope channel properties. I do that, and the note plays on C5 regardless of what I select. If I try to select anything higher than C5, the actual sound plays lower, and selecting anything lower than C5 makes it play higher. If I try to set a note range lower or higher than C5, it simply doesn't play at all. Can anyone tell me what I'm doing wrong here?