@AlexLJones 1) Log in to your Sky router IP and use your admin credentials 2) Navigate to the "Advanced" section and select "Lan IP Setup" in the menu. Find the checkbox right next to "Use Router as...

@Niceguys Which speeds are you trying to get on your devices wirelessly?

if people are interested in how to remove ports in Deco M9 created by uPnP let me know.

the problem I think is that you have two mesh networks conflicting. The Deco One with the Sonos One. Try to change the channel on the Sonos, you have the option from 1, 6 and 11. I would suggest 11.

I think this is due to that deco M5 doesn't support Wifi 6. I might be wrong :) Your iPhone 11, for example, supports it.

worth trying it, in the advanced section of the deco app under router settings have you enabled "beamforming" maybe that could help?