Often a reboot of the Beam & surrounds is worth a try and if all are running on your WiFi and not wired, maybe try a different 2.4ghz WiFi channel on your router .. suggest you fix that channel to either channel 1, 6 or 11 and use a channel-width of 20MHz.

The surrounds use a 5ghz connection to the main player and that can sometimes be interfered with by other wireless devices close-by. Typical things that may interfere are baby monitors, or solid objects between a surround and the Beam,  so perhaps look at that aspect too.

Thanks, am with Virgin media so will give that a go.

 What is frustrating is that the speakers are detected and work - for a bit - before disconnecting. It is also not consistent ie sometimes the SLs are not visible in the sonos app and therefore understandably don’t work, but sometimes they are visible and still don’t work. 
 

The suggested channel change on the router will likely help to sort the issues. The various VM ‘Superhubs’ auto-select their channels on startup/update etc. So fixing your WiFi channel is perhaps worth doing anyway.

Thanks v much. That’s my job for tomorrow!