Devices not connecting to WiFi

[#1]

Hi everyone, looking for some help/advice if possible. I moved house recently and changed to PlusNet but I have struggled to get some of my devices connected to the wifi. Smart TV, computers, laptops, phones etc are all fine but I have several Sonos speakers and a few other devices that just won't connect. I'm using the 2704n router supplied by PlusNet. Having looked up the specs for the Sonos speakers they need 2.4Ghz and 802.11b/g. My router isn't dual so only provides 2.4Ghz and I've gone into advanced settings to change from b/g/n to b/g but still nothing. Distance to the router isn't an issue as some are less than 3m away and in direct line of sight of the router. Connecting via an ethernet port isn't really an option as I have 6 speakers throughout the house. Any suggestions?

[#2]

@alan83  Welcome to the forum.

Have you tried a factory reset on the devices that won't connect and setting them uo from scratch?

[#3]

Moderators Note
This topic has been moved from ADSL Broadband to My Router.

[#4]

@alan83 - how many Wi-Fi devices do you have in total? There's a pretty stingy hardware limitation where the 2704n is concerned that could be causing you problems.