If the audio and video are out of sync when playing a disc, attempt to play different discs in the player. If the issue occurs with only the one disc, then the sync issue is most likely related to that specific disc. However, if the sync issue continues with every disc, then it is most likely a timing issue caused by the processing of the audio signal when using a digital optical cable.
If the audio from the disc player goes into a TV first and is then output to a home theater system using a digital optical cable, check the TV to see if it has an audio delay or audio/video sync setting in the menu. Although not all TVs do, some have such a setting under an option called SPDIF. If it does, manually make the adjustment in the TV menu to synchronize the audio with the video.
When the disc player (or TV) is connected with a digital optical cable to a home theater system, check the home theater system to see if it has an audio delay or audio/video sync setting. If so, manually make the adjustment on the home theater system to synchronize the audio with the video.
NOTE: Audio delay adjustments usually range from 0ms to approximately 250ms.
If the issue is unresolved, service might be required. The Sony® eService Web site can assist you in obtaining service from a Sony Service Center or locating a Sony Authorized Servicer.