For a 4.1 system with Sonos, you won’t be able to use the the Naim amp.

Your front speakers are already set properly, with the Amp driving front right and front left, with an interpolated center channel. This Amp will also feed either a Sonos Sub, or a self powered sub, but not an unpowered sub, that output is line level.

Here’s where things change for you. In order to drive the surround speakers, and get the surround signal from your front Amp, you’ll need a second Sonos Amp, which ‘bonds’ with the one driving your front speakers. No wires required between the two Amps, they use a ‘hidden’ 5Ghz channel to communicate. The subwoofer output on the rear Amp is turned off when in Surround duty. 

Thanks,

Oddly it is my rear speakers that are Sonos connected at present but I get your advice thanks. 

Another Sonos amp so there is basically one front and rear that are bonded wireless.

Sounds like the only way to go and use some of what I have easily. 

Cheers Joe.

Thanks have fronts set up with first amp and sound great. Added the rear amp and in-wall speakers as surround . Don't really hear anything out of these yet even with movie playing. Checking out tv sound out settings. 

Joe

You’ll need to test with a source that was recorded in dolby digital 5.1 audio.  Sonos won’t create/simulate surround sound from a stereo source of TV audio.  You could also confirm that the rear speakers are setup correctly by setting the room to ‘full’ for music streaming sources (not TV) so you’ll stereo from both the front and rear speakers.  

Thanks. Will do that. and yes the speakers all work on music streaming.

I suppose there are 5.1 dolby test sequesces on youtube or other streaming services as well?

Cheers

Joe

YouTube, for the most part, only has stereo content. 

You’d need to go to a streaming movie channel, or the like, in order to get 5.1. Or a local channel, playing a recent movie. Don’t trust sports, or news, for sure.