[postalbyke]

Are you talking about when manning the station yourself?

Are you looking at the bearing on the notepad (the number in the upper right) or on the sonar cabinet (the needle pointing to the bearing)?

If you're looking at the bearing the needle is pointing to, there are two possible errors:
parallax error (the camera is not lined up with the center of the readout)
or
alignment error (the needle is not lined up with the center of the readout).

Or some combination of the two. When I use that station, I take bearings from the numerical readout on the clipboard because I have noticed a parallax error when doing the "hard work" myself.