router dropping devices/not allowing them to be added

plemans-

thanx for trying to help

seems since i downloaded the app i can't log in on my desktop-go figure. I did run the sped tests and they were great.

and yes it's currently connected to the wifi

ok-to answer your questions

1. currently 32 (but does change to 34) devices. Unfortunately most of the devices (in fact, all) are 2.4 gHz which limites where I can add them.

2. firmware version V1.0.4.68_10.1.75 just downloaded this-couldn't get it to download-kept getting the rainbow eternal circle of death when I tried). 

3. Cox provided an Arris Surfboard SB6190 DOCSIS 3.0 Cable Modem, which is hooked up to the router.

Hope this helps as I have more to add to the router-i am considering a mesh with 2 sattelites as the house is a 1 floor "H" shaped house. the router currently sits 10 ft off the ground slightly off center in the middle bar of the "H". All the interior walls are wallboard and wos-no metal suppoert beams that I know of.

Several people have recommended the mesh, as (I think i got this right) the devices attach to the satellite which then attaches to the router-i guess they act like hubs and control the "traffic" locally. These systems are expensive but if it solves the problem and eliminates the aggravation then great.