I originally bought set of 3 Deco M5's

they were good but still left a few weak spots in my house.

I thought that changing them to M9's would solve this rather than adding more M5@s and add a few benefits (zigbee etc.)

having place them in same spots as original M5 units (plugging in TV's etc the signal is not any better.

When checking the signal

I get a very congested message.

The M5's were able to reconfigure / optimise channels to give a better signal, but I can't find anywhere for the M9's to be asked to do this.

Is this correct?