Update. It does not seen that I can use RE300 Extender when I use Access Point mode, its seen that you need Router mode, but then my Sonos does not work... Or is it any other way to make Sonos work...

@Pazza I could not connect my Sonos One and Sonos Beam speakers to the Deco M9 Plus system (ie on the same WI-FI network). It apparently has to do with both systems running mesh and therefore you...