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Just installed into my new Android TV box. Everything's good except the audio sync issues. There's a second delay between lips and sound. Every movie sounds like those old Chinese martial arts movie. I tried to adjust the slider bar but its not helping at all. Does anyone have any suggestions?
I started up a movie and the audio was fine.......then when I paused the movie for two minutes.....and played again.....the audio issue came back. Now the voice is ahead by a second. Not sure what to do.
My spdif output is 225ms ahead of video. Does this seem familiar to you? Audio output through HDMI is sync.

My setup:
MX-box -hdmi- TV
MX-box -coaxial- receiver
TV -toslink- receiver

My receiver doesn't have HDMI, so I have to use coaxial, main reason to go for G18REF.

Standard I have to delay audio in the receiver for 50ms to get lipsync with the TV. I get no echo when turning on audio on TV and receiver simultaneous. This can be checked very good with the opening scene of Adele - Live at the Royal Albert Hall. This scene has close-up slow piano strikes. You can clearly see when the thumb hits a key and thus you can adjust lipsync this way. If I play this DVD and output AC3 to my TV and then from my TV to the receiver I get perfectly sync audio. Unfortunately my TV can't passthrough DTS thus I have to use coaxial as well.

Now when I use the receiver on coaxial input I have to delay audio to the max amount of 200ms in my receiver and then delay audio in XBMC with another 75ms to get sync. Thus 275ms in total. This is exactly the sum of 50ms and 225ms.

I remember this problem existed before but then it was on HDMI also. Unfortunately I can't find any info on it. Apart from this post: http://forum.xbmc.org/showthread.php?tid=181739&page=3 and this old pivos post: http://www.pivosforums.com/viewtopic...=3114&start=10

Interessting information when using "Fixed" audio settings:
When I configure the audio settings as 'Fixed' with whatever samplerate I get the same sync issue on HDMI. So audio is 225ms ahead of video when using Fixed samplerate. Somehow this has to be related to the spdif issue. When using Best match or Optmized the audio stays sync over HDMI.

The difference is that Fixed resamples the audio to PCM, so using Fixed you can't get 5.1 over spdif.

Could someone confirm audio is out-of-sync when using Fixed. In Mbox settings I selected HDMI passthrough as audio device. I think maybe being able to choose the audio device for passthrough and normal output in Audio settings would help to solve this weird behavior


All this only happens when using a Gotham build (Linux, OpenELEC, official Android). With Frodo everything was fine, so it seems to me this has been caused by the AE rework.
I have retested some builds to be sure. Frodo 12.2 compiled with amcodec switch has no problems. All tested Gotham builds have problems, Helix nightly of 25-07-2014 has problems. So seems definitely an AE issue, any dev that can shine a light on this?
I have found that when I pause most playing videos and resume on my Pivos XS and DS boxes - the audio is out of sync with the video even though it was fine when I started playing.

This is most noticeable when watching something like the Daily Show where the host is speaking but it actually happens all the time. Most of my videos are x264 encoded - playing from an smb share. Audio is stereo through the TV speakers.

It's happens so commonly I have a key bound on my remote now to bring up the adjust audio offset function. This happened on my DS as well.

I have found that on my Pivos DS I always needed to adjust the delay to 0.225 seconds behind - which resynced things. With the Pivos XS - it's consistently fixed if I put the delay at 0.125 s.

This happens on XBMC 13.2 beta 2 (sideloaded). Does not happen in Windows on my other box.
Actually I think I just found a repeatable way of triggering it.

It seems that if the video is paused long enough for the screen to dim. When I press play twice to restart it comes back out of sync and stays out of sync until I adjust the delay to 0.125.

Just did it with an mp4 and with an avi file.
I think is a problem with permission, In case you TV box are amlogic try this steps:

http://forum.xbmc.org/showthread.php?tid...pid1765306
For my audio sync start normally and increase desync time, Example start on 0ms desync and after 10 minutes increase to 1000 ms, Is a problem with permission, Please check this post: http://forum.xbmc.org/showthread.php?tid...pid1765306
Permissions are set properly at boot by XBMC which has been granted super user rights: http://www.youtube.com/watch?v=i4tynXxOP64 So I don't think that is a problem.

In short this is my problem:

AC3 DTS over spdif -> 225ms sync error
AAC transcoded to AC3 over spdif -> no problem
AC3 DTS downmixed to PCM over spdif -> no problem

When audio is untouched by XBMC, the audio sync error appears. unfortunately I can't test this on HDMI.
This is NOT permissions! This is a problem with Gotham/Helix, in Frodo things are fine. i've tested this with multiple versions, different settings in android and different settings in xbmc, xbmc has been granted super user rights and sets file permissions at boot: http://www.youtube.com/watch?v=i4tynXxOP64

This also happens with the OpenElec and buildroot Linux builds on a g18ref device.

in short:
AC3 DTS over spdif -> 225ms sync error
AAC transcoded to AC3 over spdif -> no problem
AC3 DTS downmixed to PCM over spdif -> no problem
Crap, just noticed transcoded AAC to AC3 plays out-of-sync as well. So only the PCM downmixed material plays sync.

FORGET I SAID THIS.


AAC to AC3 transcode plays with audio/video sync just fine
Anyone else experiencing this?
Anybody knows if FernetMenta hangs around this forum?
he is on holiday for couple of weeks. yes we do that occasionally Smile
maybe some one else could answer as well.
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