The problem is with any iPhone or iPad. It seems to take forever to actually list the WiFi networks. An extender downstairs always shows up immediately, D-LINK PowerLine which provides an access point.
The only thing I can think of is that it uses WPA and the Asus WiFi is set to use WPA2. Would this cause this type of behaviour? Also have the same problem with my Nest as well, happily connects to the D-LINK extender but refuses to connect to any of the Asus wireless SSIDS.
plusnet Unlimited Fibre (FTTC). Sync ~ 63.83/15.7Mbps