I installed a system for a customer a few months ago. The equipment is:

LG 65LA9700
Yamaha RX-A730
Yamaha BD-S673
Martin Logan Motion6
Martin Logan Motion4's
Sunfire SDS8
ProControl Pro24.r
ProControl ProLinkR
Samsung SMTH series cable box

From the very beginning the customer has had issues with lip sync from the cable box. Any attempts to manually adjust the lip sync delay in the Yamaha receiver do not help because it seems the audio delay is different on different channels. Some channels seem to have no problem, other channels seem really bad. This suggests to me that the issue is on the cable side of things.

So the customer had TWC replace her cable box, but that did not help. Next time I am at her house I will test the cable signal strength at the box location, but the customer is not complaining of pixellation or any of the other typical signs of poor signal strength.

Currently, all video processing is turned off in the Yamaha receiver, and the lip sync is set to auto.

Any suggestions on how I can help this customer?

Thanks!

Have you tested this with the TV off?

No, really
Bypass all equipment, direct connect to TV
If possible, digital CATV feed direct into TV
Do the same issues occur?


This artifact really bugs me, others can not "see/hear" it?

Have the same issue in Northwest KY. some channels are fine, others have issues. TW video service in this area is terrible. Most of my customers in this area have DirecTV or Dish.

I've had the same issue the TWC. If you plug the cable box straight into the TV and use the TV speakers to test you will see the exact same problem. Very, Very annoying but nothing you can do to fix it at least completely. It's hard to fix a moving problem. Channel to channel and show to show.

Troubleshooting is the art of pinning down where the problem is, whether it is in one thing, another thing, or the combination of several things. The fact that this problem varies from channel to channel, without changing anything at all about
the TV,
the AVR,
the wiring,
the speakers,
hell, the nightlight,
but only varies along with changing the channel of the cable box,
means that the problem is in the internal operation of the cable box.

If it should happen that the problem varies with the resolution of the image, say an SD image is synched but an HD image is not, the test to verify this is going directly from the cable box into the TV; if it might perhaps be an issue of the TV messing up, then replacing the TV might show that. A difficulty here is the amount of time it would take to survey channels and TV shows that always or never have this problem, then the time to compare the results with two different TVs. And of course you're using HDMI, so you can't connect two TVs at the same time and just turn their volumes up and down; connection of two monitors introduces its own problems.

Speaking practically, if the customer has a 65" TV and you can spend the time and money to prove that it's the combination of the cable box and the TV, what are you going to do? Change cable companies? Replace the TV? It's quite possible that in the final analysis this is just one more HDMI problem with no solution.

I have seen the same thing with Time Warner cable in San Diego.
Normally it is worst on 1-2 of the local networks. Seems to be something on the broadcast side.
For like a year or so, Directv had the same issue with a couple of the local channels.

Maybe DirecTV could tell Time Warner how to fix this, and in return Time Warner could give DirecTV the Dodger channel.

I ran into this here with Charter a few years back. The "fix" at the time was to hookup the cable box HDMI just for video, and use a digital audio connection for audio. This may or may not help you, but since then we haven't been back to troubleshoot this....... or the client got used to certain channels not syncing and understanding it is/was a Charter issue.