Honeywell HMC6352 Compass Module

CumQuaT

I've calibrated this thing a few times now, but it still will make jumps of 10 or 15 units at certain points during its rotation. They're consistant, too. I'll get the readings as I slowly turn, and it goes something like:

76, 77, 78, 79, 91, 92, 93, 94... etc

Anyone had this experience? There is nothing metal or magnetic near it...