Lip Sync issues are complex, and I really do feel for those experiencing them, they do affect many platforms not just Sky Stream.
But I feel Sky needs to do far more around manging customer satisfaction around this issue.
Why? Because for many, including myself, SKY UK is seen as a premium TV service, if you can afford it, you have SKY, but SKY also sports and SKY cinema, but in return you expect the best.
This is where I feel SKY are starting to fall down, there is clearly a problem, and from a technical perspective its well know.
I expect when the signal leaves the SKY Stream box the Picture and Sound will be in sync, the problem people (and SKY) are facing is what happens next...
For example, people that use soundbars and ARC or eARC , (I'm NOT excusing the issue, but trying to explain the complexity), the image and sound go the TV, the TV processes the image and sound based on the settings, which could mean anything, so a TV with a high amount of picture processing could delay the image by a few milliseconds, yet send the sound out to the sound bar without delay, this will cause a problem...
But it's only the start....
The soundbar itself could cause further delays while processing the sound, so causing the sound the fall even move behind the image.
HDMI right now does not send any feedback to the SKY Stream Box from the TV or the Soundbar so the SKY Box doesn't know how much time each device needs to process the image or sound.
This to be honest in a inherent problem with the current HDMI standard.
However I think we all agree SKY Stream is a premium product so it needs a solution.
I think right now there is not one, that is the problem....
However, what may help some people, but NOT all is f SKY could do is publish rsome ecommend settings for equipment that is problematic, that is all I can suggest.
I'm sure many people will criticise this post, and poop on that I have said, that's fine, I'm not an expert so cut me some slack, all I'm trying to do is explain why, it my be hard for SKY to fix, but they do NEED to fix...