Can you describe the Sonos setup in more detail - How is the Arc and/or Port linked to your projector? What are you using as HT surrounds? How far away are the surrounds from the Arc?

Any devices wired to the local network subnet?

If using WiFi what channels and channel-widths are in use?

Make/model of router and are there any switches (managed or unmanaged) involved in any of the wired connections?

Hi Ken thanks for xcoming back to me.

Sonos setup

Arc+sub+2xSOnes+port.

~4meters distance from Arc to surrounds

-3 metes between surrounds 

Wifi set up:

2.4Ghz, access points on each floor, 

Home theatre set up 

sonos+chromecast+JVC projector 

Jvc connected via hdmi to port (sound)

chromecast via hdmi to JVC (picture)

sonos port and Chromecast working in the same 2.4ghz wifi access point

Best Tomek

I’m not understanding the above - is this an HDMI-ARC connection and are you using some kind of extractor/converter to connect to the Ports RCA Analog line-in? If that’s the case are you not noticing an audio delay with the video on screen here? - my thoughts are if you are using the line in as a ‘stereo’ source to the Arc then that maybe your issue. However, if using a stereo source, I’m baffled that you are getting any audio at all on the rear HT channels? Perhaps I’m missing something here? Can you ‘kindly’ describe the link to the Sonos Port in a little more depth please, thanks  

Hi Ken

There is no physical (cable) connection between arc and JVC projector. Sonos port works as a hub that connects JVC and Chromecast to the entire Sonos system. 

Yes I realise that, but you mentioned that the Port is connected to the Projector using HDMI which has me baffled, as there is no such connection on the Sonos Port. I assume you’re using a connection to the Port line-in from a DAC or extractor - anyhow to stop the dropouts may depend on whether you are ‘grouping’ the Port with the Arc/Surrounds or if you are selecting the line-in input to play the stereo only audio?

I assume you’re just playing stereo on your HT setup, rather than Surround Sound too?

If using the Port line-in for your Projector audio output, as I suspect …and grouping that input with your Arc/Surrounds, but seeing audio dropouts on the HT, then see this Sonos support link for the suggested fixes…

https://support.sonos.com/en-us/article/line-in-audio-stops-or-skips-when-sonos-rooms-are-grouped

If that’s not what you are doing with your Projector/Sonos setup, then perhaps post back with some further detail.