@Chrisee
You may well be correct, but I was merely guessing. The Comcast "streaming platform architecture" is the only thing that sets Sky apart from other streaming services and devices.
The small (but obvious to me) lag that accompanies the Sky Stream UI at all times is symptomatic of the platform being server based. Someone on another post labelled it 'friction' which I think is very appropriate.
No other streaming device on the market uses the same architecture (as far as we know) in the same way, so it's safe to assume that it's somewhere in this architecture that the problems lie for those of us who have or have had issues with the service.
When I had Stream I too passed the raw audio directly to my Denon AVR then through to my TV. I experienced the odd random audio drop-out and random lip sync errors between apps and live channel streams. The same would occur if the puck was connected direct to the TV with passthrough to the AVR via eARC. Nothing I tried in a year of ownership (including a replacement puck, a different TV and a different AVR) would solve it with any level of consistency.
The vast majority of happy Sky Stream customers are typical mass-market Sky customers who aren't interested in the minutiae of the service - audio codecs, lag, buffering, etc. They don't notice the odd drop out or may not even know what Dolby Atmos is, let alone have a means of processing it. They just want to turn on their telly, press a button and watch Corrie. That's why most of the questions on here relate to connection issues - the mass market aren't yet used to maintaining a robust, fast and stable broadband connection in their home in order to receive their TV service.
For me, this is the key to Sky Stream. I keep saying - it's a mass market product and for most people it does the job and works well. Dolby Atmos is not mass market. If you did a poll of Sky customers only a small minority would be able to tell you what it was. Sky don't even highlight when Dolby Atmos is available on content particularly well.
Other hardware manufacturers produce cheap mass market products which output Atmos perfectly well. Amazon Firesticks have been doing it for years. I don't think I've ever experienced an Atmos dropout with either of the two I've had.
This leads me back to Comcast's "streaming platform architecture" - it's the one unknown quantity in all this. As you say, they've never talked about it because it's clearly proprietary, and I think the Atmos issues (and probably some of the other issues) lie somewhere within how it works.
