A method and apparatus for dealing with undesired deviations of servo burst component magnitudes, as compared with nominal magnitudes, is provided. Inaccurate servo burst magnitudes can arise from components which are misplaced, often from an inaccuracy in a trimming operation. In one aspect, a value indicative of the shift of a component null point is measured and used to calculate a burst amplitude correction factor. Knowledge of system dynamics can be used to calculate a track shape that can be used in calculating the correction factor. Values indicative of track shape can be related to transfer functions of the disk drive controller and plant. In one embodiment, information indicative of repeatable runout is convolved with a function of the transfer function of the controller and plant, and the result is used for calculating a burst component amplitude correction value.