Just a heads up if anyone from sonos is looking.  I asked around in reddit as well and I am hearing other people on 14.8.1 are having the same issues.  Any acknowledgment of this being a known issue?

See the pinned reply in the following thread:

I'm also having the same issue and it's real unpleasant.

If anyone from SONOS is looking: Diagnostic sent # 698574705

Thanks!

Same thing happening to me. 
 

I upgraded my Beam (gen 1) to an Arc a couple of days ago but today the surrounds (a pair of Ones) are just slightly out of sync. All up to date on 14.8.1. 

Have you perhaps ‘grouped’ the Ones, rather than ‘bonding’ them to the Arc? I did a similar upgrade and moved the Beam to the main bedroom, but both HT systems (Arc & Beam) are working fine here with Sonos One (gen2’s) as their bonded surrounds.

I’m not sure I know the difference. Maybe I did things the wrong way but I just unplugged my Beam and then reset the Ones and paired them as surrounds. 
 

They show as individual surrounds when I go into the room (all I have is the Arc and pair of Ones). It seems to work for a while if I power down the Arc but out of sync again a few hours later. 

So just to be certain @ben ww, presumably they all show in the ‘Settings/System’ area of the Sonos App as one room only, something similar to “Living Room (+LS+RS)” depending on your chosen room name for the Arc.

If so and you continue to have difficulties keeping things in sync, then the next time it happens, submit a system diagnostic report within 20 minutes of hearing the issue and note it’s reference number. Then chat/contact to Sonos Support Staff via this LINK and see if they can glean anything from the diagnostic.

Hope you manage to get the issue resolved.

Thanks! They definitely show as one room with (+LS+RS) so I’ll do that.