How does A/V Sync work on Sony Blu-ray players?

[Ballardian]

Like many people I've had problems with the sound being out of sync with the picture on the new Twin Peaks Blu-ray set. I managed to solve the problem almost completely by adjusting the A/V Sync function on my BDP-S480 Blu-ray player which (the manual claims) delays the sound output in relation to the picture output.
My question is: why does this fix the problem on the faulty parts of the disc but not send the good parts of the disc out of sync? I'm really glad it doesn't but the reason is a mystery to me!

[Anonymous · Accepted solution]

Hi there

As far as I understand it, when A/V Sync is enabled, it delays the audio in order to compensate for the lag between the bluray/dvd player and TV.  HDMI can introduce a slight lag, as well as TV image processing. 

So why does it work in certain areas on a bluray disc that needs it, and at the same time area's where it doesnt - To be absolutely honest, I dont really know - and unlikely to know as this could be part of a "trade secret" - We could just conclude that it works due to wizardry magic!  Could it be that this function also enables the scanning of imbeded metadata (just guessing). 

My advice is to contact Sony Support : HERE and see if they can/will explain it.

Cheers

[Ballardian]

Thanks. The only theory that makes sense to me is that the A/V sync adds more delay to the processing of both sound and picture, so it has more time to match them up. I don't know if that's possible.

[Anonymous]

I guess its possible - but then how does it know that certain parts in a movie is in sync and others arnt? Who knows !