Audio out of Sync with Video

Discussion in 'Archived Threads 2001-2004' started by William_K_F, Jan 2, 2003.

  1. William_K_F

    William_K_F Agent

    Joined:
    Feb 4, 2002
    Messages:
    33
    Likes Received:
    0
    Trophy Points:
    0
    I have a Pioneer Elite VSX-45TX receiver and have digital inputs for the Pioneer Elite DVD DV-05 and the Dish PVR-500. I find that when their is dialog the movement of the mouths on the screen does not match the sound of their voices. It appears that there is a slight delay in the voices compared to the screen movements. This is very distracting and I would like to correct it if possible. I estimate the delay is around 30 miliseconds.

    One possible reason just occured to me: I have the video going straight to the television instead of through the receiver. I do this to get the best possible picture, but maybe the receiver can make sure the two signals are syncronized together? Any ideas on whether this is worth trying? The DVD is component video and the Dish player is S-Video. I'd have to buy more cables to do this so want to make sure it will help before trying it.

    Is this a known problem? Is it due to the time it takes to process the digital signal into analog?

    Thanks.

    -William
     
  2. Michael Mohrmann

    Michael Mohrmann Screenwriter

    Joined:
    Dec 30, 2001
    Messages:
    1,394
    Likes Received:
    0
    Trophy Points:
    0
    William,

    That's interesting, because it is usually the video that is lagging behind the audio. Scalars, line doublers and such tend to delay the video's output, requiring a delay in the audio to sync up. Some receivers and processors have a feature to delay the audio (generally by source) to sync up with the video.

    I am not familiar with the 45TX, but if it does have such a feature, you may want to check to see that it hasn't been accidentally set. Other than that, video/audio sync problems are generally the fault of the source (DVD player, sat dish receiver) or the source material (DVD, sat dish signal). Is the sync problem for all inputs in your system?

    Michael
     
  3. William_K_F

    William_K_F Agent

    Joined:
    Feb 4, 2002
    Messages:
    33
    Likes Received:
    0
    Trophy Points:
    0
    I performed an experiment: I ran the DVD analog outputs directly to the TV and did an A/B comparison between the TV and the digital output through the receiver.

    It appears that the analog output to the TV is synchronized exactly whereas the digital one is very very slightly delayed, maybe closer to 20 milliseconds.

    When I run both at the same time, the voice gets an echo quality like there are two people speaking.
     
  4. William_K_F

    William_K_F Agent

    Joined:
    Feb 4, 2002
    Messages:
    33
    Likes Received:
    0
    Trophy Points:
    0
    I extended my experiment by sending both digital and analog to the receiver so I have three sources to compare.
    The analog through the receiver appears to sync up better although I still get a slight echo effect (although much less than before) when I listen to the TV analog output simultaneously with the receiver.
    It would appear that the digital signal processing is the source of the most obvious delay. Now the question is how do I resolve it, other than switching back to analog [​IMG] ? Would sending the video signal through the receiver resolve it as it might delay it too?
    Thanks.
     
  5. Greg Kolinski

    Greg Kolinski Second Unit

    Joined:
    Oct 13, 2002
    Messages:
    331
    Likes Received:
    0
    Trophy Points:
    0
    I have the Dish 4700 series reciever,it does the voice /picture problem every couple of months.Just pull the smart card out ,shut down the dish unit for a minute or so,and all should be well.[​IMG] At least that what fixes mine.Pulling the smart card is the first thing to always do when a Dish product does weird stuff is what I have learned.I guess it just gets confused some times
    Greg
     

Share This Page