I noticed that when the compass is just sitting on the table it points to where I know north is, but when I pick up it immediately swings anywhere from 10 to 30 degrees to the east.
This could be a serious issue if I ever got lost and had to rely on a compass to find my way...especially since there is such a large difference in the amount of the degree. Last night, when I noticed it, it was off by 30 degrees. Then I checked again before writing this and it was only off by 10 degrees.