Connect (Not Connect Amp) with local speakers out of sync with rest of Sonus network..

And is the soundbar Airplay enabled?

Hi. You say a normal source through the Sonos app. But you are playing the line in source through the Sonos app aren't you? I am not clear whether you don't regard line in as a normal source or that you are not using the Sonos app to play it (somehow)

John: My regular config is the line-in through Connect (from Airplay) -- what I refer to as 'normal' would be a source coming from the Sonos App for instance.

The 'Airplay' input is coming from an Apple Airport device through a regular line-in 1/8 audio connection. The fact that it is Airplay is incidental to the issue.

And is the soundbar Airplay enabled?

No -- The soundbar is simply an amp/speakers slaved off the Connect through Digital COAX (SP-DIF)

Can we clarify that

I do group together (Playbar + Play:3 + Play:1) to the Connect.

means that the CONNECT is part of the group, and not just providing the Line-In source (whilst playing its own Line-In independently)?

Can we clarify that

I do group together (Playbar + Play:3 + Play:1) to the Connect.

means that the CONNECT is part of the group, and not just providing the Line-In source (whilst playing its own Line-In independently)?Sounds like a plausible line of enquiry. I would expect the Autoplay "room" for the line-in to be the Connect itself, and then the grouping to start from the Connect and group it to the Playbar, Play:1 and Play:3. In that setup I cannot conceive how the soundbar could be ahead of the other speakers, nor how anything would differ between using the line-in source or any other source.

[In that setup I cannot conceive how the soundbar could be ahead of the other speakersUnless the soundbar features a flux capacitor.

I will have to try the inverse : Connect grouped as part of a 'normal' source (through Sonos App) -- in this case I would expect the audio to be in sync, but I will have to verifyThere is nothing "inverse" about it. The grouping is identical, the Sonos App is used in all cases.

The SONUS App can be the source of content from within the App or the input can come from the TV though the Playbar or from the line-in on the Connect. In the case of playing content from within the App (e.g. from a Sonos playlist or 'on this iphone), the sound is in much better alignment. When selecting the source from 'line-In' from within the App, which is the Line-in on the Connect device: this is where the audio is out of sync more noticeably. Yes, the grouping is identical, but the source for the content is very different, which is why i refer to it as inverse (probably should have used the word 'alternative' to describe where the source content is coming from)

My theory being that the Connect, since it is both the input source for the content as well as the audio out for the local amp/speakers, has a faster path for the audio to be fed to its local audio out connection and that by the time the audio signal is processed by the connect, converted into the mesh for the rest of the grouped devices, there is a delay with the rest of the speakers.

The simple fact is that when using the identical grouping of devices, there is a noticeable difference in the sound being in sync when the content comes from the line-in on the connect vs when the content comes from 'within the App.' The amp/speakers attached to the Connect is slightly ahead of the sound for the rest of the mesh in this case.

As an (old!) electrical engineer, I can understand that the local audio feedback in the Connect could be faster than the rest of the system, given that the audio signal has to be converted, first into digital form, and then further processed into the wi-fi (and LAN) mesh that Sonos employs to route audio to all of the grouped devices. The local audio out circuitry could be a much faster path since it could conceivably not have to go through as much processing. I have tried both the standard RCA output as well as digital coax outputs of the Connect and both are exhibiting the same behavior. I have also tried a different amplified speaker (A Bose mini) connected to the Connect and the issue still exists.

This is why I would like to delay the Connect's driving of the audio signals to the audio out ports to compensate for the processing needed by the Sonos system. The simple answer I am gleaning is there is no way to do this (delay the local audio a few hundred milliseconds or so) to align the sound. The fact that the sound is out of sync is real, though...

I do enjoy the Sonos system and this is not a huge deal breaker for me, but a final tweak I have been trying to resolve for my setup. I had an extra old Vizio soundbar that I replaced with a Sonos Playbar for my home theater. I am trying to make use of the old Vizio soundbar in some way. Since the Connect has an audio out capability, I found that to be an obvious thing to try --- but it appears not to be workable.

As an aside, the Connect works great as a generic input path for anything that I can play on my iPhone through the Airport device -- an easy way to connect Apple's Airplay network with Sonos. Simply connect the audio output of the Airport to the Audio in of the Sonos connect. With this, any streaming content I can play through my iPhone, I can route into Sonos by selecting the Airplay output from the iPhone. Examples being a web podcast from a favorite sports team that might only be available through that team's app, and not Apples podcast app. Sonos does a pretty good job of capturing a lot of streamed content, but not everything, so this path allows for anything that can be routed to Airplay to be pulled into the Sonos setup.

I don't think your description matches h:ow Sonos syncs. I suggest calling Sonos Support so they can take a look at your system. It is not impossible that you have a failure in the sync timing mechanism.

My theory being that the Connect, since it is both the input source for the content as well as the audio out for the local amp/speakers, has a faster path for the audio to be fed to its local audio out connection and that by the time the audio signal is processed by the connect, converted into the mesh for the rest of the grouped devices, there is a delay with the rest of the speakers.
I'm sorry to say that your theory is simply based on a false premise. The same audio pipeline -- and delay -- is used for local audio as for that which traverses the network. Indeed these forums are replete with threads from users explicitly requesting a 'direct mode' to play local Line-In audio with zero delay, because the option doesn't exist.

Multi-room sync is fundamental to Sonos. If, despite grouping and ruling out external effects (such as downstream DSP soundfield processing), you still lose sync then you could suffering from a rare hardware fault. Submit a diagnostic, post the number and consult Sonos.

For what it's worth I just tested a Line-In to a ZP80 (CONNECT's precursor), and grouped players are, as expected and by design, in sync with it.