Lip Synch issues

[birdog1960]

Lip synch is off on 2 separate systems for me. One is through a receiver via high speed hdmi. One is through TV speakers. Both have video ahead of audio but it doesn't seem consistent. Sometimes it syncs. Seems like that would mean the source is the problem. Both are steaming through the same model fire stick. Anyone else noticed something similar with different sources? Direct stream seems the worst.

 

[RayDunzl]

My TV has a setting to choose a delay for the sound.

Does yours?

And yes, sometimes, the sync varies with the program.

 

[birdog1960]

My TV has a setting to choose a delay for the sound.

Does yours?

And yes, sometimes, the sync varies with the program.

in my case the audio lagged behind the vid. finally traced it to the fire sticks- apparently a common problem. They have a bouncing ball with test tone recently added to the app in settings.

 

[amirm]

Lip synch is off on 2 separate systems for me. One is through a receiver via high speed hdmi. One is through TV speakers. Both have video ahead of audio but it doesn't seem consistent. Sometimes it syncs. Seems like that would mean the source is the problem. Both are steaming through the same model fire stick. Anyone else noticed something similar with different sources? Direct stream seems the worst.

All the time. Even when watching a single channel lip sync changes from clip to clip. Long lost is the attention paid to lip sync when we had analog TV. All you can do is get it close.

Technically it is a challenging problem in digital/streaming as the audio and video clocks are never multiples of each other. Nor are they always the same at playback. Getting them to stay in sync sometimes is more of an art than science.

 

[RayDunzl]

It syncs right up if I take my glasses off, but then I can't read the fine print on the Medication and Financial commercials.

 

[Dunring]

I have a few Firetv sticks, one of the best things is if your router has 5ghz and 2.4ghz to disable the 2.4ghz network. Bluetooth uses 2.4 and the less devices you have on that frequency the better/smoother audio will be. Even the magnetron in your microwave goes off at 2.4ghz. It's a really over-used frequency. A DECT wireless phone uses 1.9ghz and has good range, and they make 5ghz mice and keyboards too if there's something near the TV like that.

 

[-Matt-]

I think 'video ahead of audio' is an increasing problem these days. Historically video processing was almost always slower than audio processing but that is no longer the case. TV manufacturers have put quite a bit of effort into reducing lag for gaming, so video processing times are now often just a few ms (especially for OLEDs).

AVRs do all sorts of audio processing, not least of which is adding delays to synchronise sound from different speakers. If you have some speakers much more distant than others then this will result in more delayed audio all round. Hence, try to get your speakers as close to equidistant as possible.

TVs and AVRs all typically include controls to increase delay audio but so far I haven't seen any that offer a way of delaying video (would require a larger memory buffer). This means that you can't easily fix 'video ahead of audio'.

Edit: Amir's point that sync chops and changes from one program to the next is also true. I try to ignore it, but it does bother me.

 

[Philbo King]

I see/hear it all the time on Amazon video streams on our Samsung TV. The amount of lag shifts (becomes greater with time) as episodes in a series are watched. It can temporarily be fixed by exiting the app and restarting it. Doesn't happen with Netflix or HBOMax, only Amazon.

The point of this post is to point out the quality of the streaming service has an effect. If you want to tweak the audio delay settings it's best to use over-the-air or Bluray/DVD as a source.

 

[birdog1960]

I think 'video ahead of audio' is an increasing problem these days. Historically video processing was almost always slower than audio processing but that is no longer the case. TV manufacturers have put quite a bit of effort into reducing lag for gaming, so video processing times are now often just a few ms (especially for OLEDs).

AVRs do all sorts of audio processing, not least of which is adding delays to synchronise sound from different speakers. If you have some speakers much more distant than others then this will result in more delayed audio all round. Hence, try to get your speakers as close to equidistant as possible.

TVs and AVRs all typically include controls to increase delay audio but so far I haven't seen any that offer a way of delaying video (would require a larger memory buffer). This means that you can't easily fix 'video ahead of audio'.

Edit: Amir's point that sync chops and changes from one program to the next is also true. I try to ignore it, but it does bother me.

The fire stick app allows both slowing and speeding up audio...plus it's kinda fun to match the bouncing ball with the test tone! btw, your point on OLED tv's apples to me. It's worse on the OLED than on a LED tv in my case. To your other point, would playing in pure direct speed up audio while still allowing surround sound?

 

[RayDunzl]

I've read (if I remember correctly, and will try to find the reference) that vision lags hearing by 200ms or so.

 

[-Matt-]

The fire stick app allows both slowing and speeding up audio...plus it's kinda fun to match the bouncing ball with the test tone! btw, your point on OLED tv's apples to me. It's worse on the OLED than on a LED tv in my case.

I typically think of broadcast or spinning disc media. In those cases it is impossible to speed up the audio. You can't play it before it has been broadcast.

..but maybe things are different with streaming. (You already have a buffer for both video and audio).

Having said that, from the point of view of an AVR, the source doesn't matter. It is still as though it is being broadcast to.

I think the only way that speeding up audio can work in a streamer is really by delaying the video.