Abstract: A videodisc playback system is equipped with a reading device that sequentially reads the key code signals recorded on a videodisc in order to discriminate field, frame, or track. A mistracking pulse generator temporarily stores two key code signals that were consecutively read from the reading device, compares the two stored key code signals and detects the occurrence of mistracking from the two key code signals, and at the same time, generates mistracking pulses in an expanded blanking time, in a number that corresponds to the number of tracks travelled in the opposite direction to the playback shifting direction when the mistracking was detected. A forced driving device forcibly shifts the playback tracks one track at a time in the playback shifting direction with every mistracking pulse impressed from the mistracking pulse generator.