If I create a new wireless SSID in Luci with Network set as LAN, without having any SSIDs setup before (all removed), an interface named radio0 is automatically created. This radio0 gets bridged with my ethernet but no wireless does work.
Than I go to the Wireless setting of my SSID and have to set the Network again to LAN (It gets unset), an interface named "Master $SSID" is created. My wireless does work again.
Happens with my Buffalo wzr-hpg300nh and Xiaomi mir3g with the current trunk.
Is the radio0 interface needed? Does it happen to you too?
I can get it away by deselecting the radio0 from Interface from Network->Interfaces->LAN->Physcial Settings->Interface.