The purpose of this module is to establish lock in both frame and line between the disc and the sync generator on the reference source module (D). Thanks to the fact that the player is equipped with RGB, synchronization of the colour subcarrier is not required. Locking is possible at the internal sync generator which is highly accurate. In this way it is possible to place, before the disc is turning, text on the screen which is coupled to a sync to which the disc will also be synchronized later. Moreover, the video signal of the disc can be synchronized to an external video or sync signal. Locking is done by adapting the rotational speed of the disc or the motor control via module F. In this way the phase of the read-out video (CV-DOC) is controlled.