To quickly start data reading operation by controlling a seek status signal so as to stabilize RPLL operation after the finish of seeking operation.

A disk drive device 10 comprises: an RPLL circuit 4 which generates a synchronization clock 11 using an inputted RF signal 18; a control circuit 6 which controls holding processing and initialization processing of the RPLL circuit 4 on the basis of the seek status signal 15 indicating whether the seeking operation is being performed; and a delay circuit 8 which controls the execution timing of the holding processing in the control circuit 6 on the basis of the seek status signal 15.