Delay in sound onset in some TV programmes.

[Windblown]

We have recently bought a Sony Bravia 55" 4K Android TV. After initial problems,  resolved when we had our aerial signal optimised, reception has been great with excellent HD on terrestrial TV and superb 4K on recorded and streamed media.  However one problem remains.

On certain sorts of TV programmes there is a delayed onset of sound at the beginning of segments, such as change of scene, change of studio camera, change of person speaking.  Delay = 1 to 2 seconds. Once initiated, sound is  properly synced with good sound and picture quality. The delayed onset has been noted at the beginning of some adverts and during news programmes, chat shows, TV drama and  game shows, but never during broadcast or streamed movies. I have started to keep a log, which I will share in due course, if necessary, when I have enough negative and positive data.  

Steps I have taken include ensuring that in 'Settings' that the system is prioritised for an optical connection to the sound bar. The sound bar, see image,  is an LG with bluetooth subwoofer. Yes, I did power the sound bar off and on after changing settings. 

Any suggestions folk? 

[daveyh64]

Do you experience the audio problems when only using the TVs internal speakers.

[Windblown]

No.  There is never a delay in initiation of sound through the TV speakers. 

I can't think what settings might change anything. 

Here are the current settings. I get the same symptom if 'using the TV speakers as the centre speaker of the home theatre system'   is enabled.  

[rooobb]

Why the digital audio output is set to pcm? It requires the TV to downgrade to stereo analogue audio instead of the original digital signal. It could be that this is not the root cause but for sure you are getting a worst sound from your soundbar....

[royabrown2]

….and a delay each time while the soundbar tries to sort out the ruins of your audio!

[Windblown]

Thanks for your reply.  PCM was the default setting, so I left it alone whilst changing other variables. 

In response to your comment I have changed the setting to pass through for digital audio. I will keep it at that for 24 hours to monitor a variety of TV programme types for delayed sound.  Given that I have already switched on the dealy adjustment feature with no improvement, I hope that your suggestion removes the need for my sound system to cope with the 'ruins. caused by my choice of settings. 

[Windblown]

Thanks for your input.   See my reply to Rooooob. 

Since my reply I have noted that the delay to sound onset is fixed. Instead, sound is no longer synced!  Switching from PCM to pass through has solved one problem, but created another! However, a reboot of the soundbar and TV have fixed that for now. 

I will monitor this. 

[Windblown]

The story continues. As I reported a couple of days ago, responding to comments I managed to be rid of the delayed sound onset. Thank you. However, sound was now not synced to the video, most notably during speech. This is corrected by rebooting the TV and the sound bar at the same time. However, the sync problem returns frequently. There must be another solution apart from rebooting. 

[Windblown]

We are still getting sync problems periodically - always corrected by restarting the TV and soundbar at the same time.

There must be an optimum setting to prevent a soundbar falling out of sync with the TV image. 

[rooobb]

You may try to play with the AV sync setting, switching it to off....