There have been numerous reports of “lip sync” problems, where the audio lags slightly behind the video or sometimes precedes the video. Perception of a sync problem is highly subjective; some people are bothered by it while others can’t discern it. Problems have been reported on a variety of players (notably the Pioneer 414 and 717 models, possibly all Pioneer models, some Sony models including the 500 series and the PS2, some Toshiba models including the 3109, and some PC decoder cards). Certain discs are also more problematic (notably Lock, Stock, and Two Smoking Barrels; Lost In Space; TRON; The Parent Trap; and Austin Powers).
The cause of the sync problem is a complex interaction of as many as four factors
1. Improper sync in audio/video encoding or DVD-Video formatting.
2. Poor sync during film production or editing (especially post-dubbing or looping).
3. Loose sync tolerances in the player.
4. Delay in the external decoder/receiver.
Factor 1 or 2 usually must be present in order for factor 3 or 4 to become apparent. Some discs with severe sync problems have been reissued after being re-encoded to fix the problem. In some cases, the sync problem in players can be fixed by pausing or stopping playback and then restarting, or by turning the player off, waiting a few seconds, then turning it back on.
A good way to test your player is to simultaneously listen to the analog and digital outputs (play the digital output through your stereo and the analog output through your TV). If the audio echoes or sounds hollow, then the player is delaying the signal and is thus the main cause of the sync problem.
Unfortunately, there is no simple answer and no simple fix. More complaints from customers should motivate manufacturers to take the problem more seriously and correct it in future players or with firmware upgrades. Pioneer originally stated that altering the audio-visual synchronization of their players “to compensate for the software quality would dramatically compromise the picture performance.” Since then Pioneer has fixed the problem on its new players. If you have an older model, check with Pioneer about an upgrade.