The present invention relates to a method for operating an optical drive system capable of reproducing/recording information from/to an optical carrier (30), wherein a position error and a speed error of a radiation spot (12, 53) on the carrier has been created due to an unreliable error signal which has been generated due to a surface defect (52). The method includes the steps of registering values of e.g. servo signals, determining the occurrence of a defect using a defect detector DEFO (22), generating a first and a second compensation signal and applying these compensation signals to the control system (10) of the optical drive system. The first compensation signal is capable of reducing the speed error and the second compensation signal is capable of reducing the position error. Thus, the application of the compensation signals immediately after the unreliable error signals reduces the position error and the speed error of the focussed radiation spot (12, 53).