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Voice out of Sync on TV (TRUE)


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I have noticed that the lips of BBC speakers (and CNN, possibly) are out of sync with the sound on my TV (Panasonic Smart TV, newish).


This has been going on for about a month. With Thai channels, it seems ok.


Apart from calling TRUE to find out, is there any known reason for this? My dish has no trees blocking it. Also, the problem is worse at some times BUT not due to rain.


Any help welcomed with thks.



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I can't remember the exact technical description, but in the old days, if you made a video (with picture and sound), and saved it to a slow (as in read/write cycle) hard disk; when you replayed the video, the sound and picture would be out of sync. If you recorded the movie (video and sound) on a high speed hard drive you didn't get this problem.
So the problem could be if you are recording the files and playing them back later, or the station is recording them and playing them back later on sub standard recording devices.

Sent from my SM-J700F using Tapatalk

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Sorry for tall the technobabble...


With almost all media content being delivered 'digitally' these days, most 'audio sync issues' are an artifact occurring either at the original head-end encoder/encrypter, *or* in the decoder/decrypter in your Set Top Box or possibly a bit later (if present) in a Home Theater System 5.1/7.1 Audio Processor/Amplifier.


Take a look at this Lyngsat graphic:




This is a typical satellite single transponder channel at 12,396 MHz (Horizontal RF Polarization) ; DVB-S2 encoding, transponder signal Symbol Rate of 30,000


In this particular instance, TrueVisions is 'multiplexing' together (1) HighDef and (13) StandardDef 'channels' (their corresponding Video and Audio data streams) into a single data stream transmitted up to the satellite, which sends it back down over south-east Asia to be picked up by TrueVision Set Top Boxes where the receiver picks out just this one transponder signal, strips out just the selected "channel's" corresponding Video and Audio data streams, applies the proper de-encryption key and digital decoder to make the Video and Audio channels available, then presents them to a Video Monitor and Sound System for normal processing.


A similar thing happens with Cable TV signals.


If your just playing the channels through a TrueVisions Set Top Box to an HDMI-connected TV then you really shouldn't experience audio sync issues.


But if you have a Dolby or DTS Home Audio System, or your TV does 'processing' then it might be occurring there. 


See if it happens on all channels, or only certain channels (like the HD, or those containing 5.1 audio).

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See how many channels are affected, then call them.

You want to collect as much data to get them to act in your favor.


As already mentioned, also try power cycling (Off/On) your TV, as the video and audio actually get sent to the TV over the HDMI cable as digital streams that the TV processes and renders  ...so it could be something about the new box and your TV.  


Maybe unplug BOTH and try again and see if it makes any difference.


If not, call True.   ...or start watching old Chinese action movies where the voice sync won't be so noticeable.

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