The audio-video synchronization process ensures continuity of displayed AV data. To initialize the process, a transport processor determines whether an occupancy criterion of a buffer storing received audio and video frames has been met. If the criterion is met, the transport processor obtains an initial time stamp value from an initial frame, and a subsequent time stamp value from a subsequent frame. Initial and subsequent parameters are computed from these respective time stamp values, and are compared against each other. If the parameters coincide, the frame is valid, and corresponding audio or video frames may be decoded and displayed. If the parameters do not coincide, a recovery process is initiated. In either event, the invention makes it possible to achieve audio-video synchronization for both live and playback modes of a digital video recorder (DVR).