I think its time to sell my Sonos set up.
I have 9 Play 1 and a boost. I’ve tried everything multiple times for so long now it’s driving me round the bend. Used to work ok with SkyQ router (14mb) when I disabled 2.4 and gave each speaker a static IP. Then it started playing up. Six months of that and I changed to BT Smart Hub 2 (150mb). Even worse even after router update. I have a small, new 3 bed detached. The router and boost are ceiling height as central to the house as possible but Sonos still refuses to be stable, constantly losing a room or part of a stereo pair.
There are just too many variables coming into play to make this system worth bothering with.