OK look at all the comments on the sit about the 1800 series.

i have done

l trouble shooting steps 

reset

wifi 

no resolve..

factory reset..didnt work

with a spectrum analyzer the 5 ghz isnt produced any more.. 

just a FYI...im switching today.. 

i have routers in several difierent buildings only 1 AX1800.. i dont recommend buying one of these..