Thanks for the input. We have a pretty decent Ubiquiti Wi-Fi set up with 6 APs in a mesh network, all with minimum signal rules set and nightly channel optimisation set so I can’t see it being the Wi-Fi signal although there is a small chance it could be.
We did have 10 Sonos units but I just gave a playbar to my in-laws to try and have less units. Some are hardwired to reduce Wi-Fi issues.
I was debating having them on their own 2.4ghz channel but then I’d need to be on the same Wi-Fi to control. For now I have dual 2.4ghz and 5ghz enabled as most IoT needs 2.4ghz.
I’ve just gone in and manually set 2.4ghz to the max channel width so will see how it goes. I can’t use 160mhz on 5ghz as my Wi-Fi 6 APs don’t seem to be compatible - annoying but unrelated.
Only problem is I can only blast the volume on all speakers when she’s not home!