Abstract: A magnetic recording disk drive has compensation for both mechanical disturbances and electrical disturbances. The disk drive's servo control system includes mechanical disturbance (MD) feedforward compensation and electrical disturbance (ED) feedforward compensation, of which either or both can be selectively enabled and disabled. In the operation of the disk drive, it is first determined that there is some disturbance that is causing track misregistration (TMR). The system is then tested to determine if the ED is greater than an ED threshold by measuring an averaged ED sensor signal. If ED is greater than the ED threshold, the system is then tested for a reduction in TMR by selectively turning MD compensation and ED compensation on and off, and determining changes in the position error signal (PES). Depending on the test results from the PES measurements, one or both of MD compensation and ED compensation is left on, and maintained on until the TMR falls below the predetermined threshold.