R8500 with ex7500 and smart connect

[Tymok]

Hi,
I’ve set up a R8500 router with the ex7500 extender.
When I use the same ssid for 5GHz low and high the extender goes bizarre. It connects to the lower channels and randomly switches to channels 100+.
At that point Devices connected to the extender switch from 100+ to lower channels causing lags and Wi-Fi instability.

At first a thought it might be a problem with the same ssid and Chanel on the R8500 and the repeater.

I tried separate ssid for 5GHz low and high.
When I connect ex7500 to the lower 5GHz channels everything works fine. Ex gets full speed all time.

When I connect ex7500 to 100+ channels I can see that the signal gets week in intervals - about every 10 seconds and the connection slows down.

Other devices linked directly to the R8500 5GHz 100+ channels seam to work stable.

When connected to the low 5GHz, devices connected to the ex on 100+ channels work stable.

I’m looking for a solution to keep smart connect ( one ssid) for all devices.

[plemans]

The 100 (ish) channels are dfs channels. Meaning they have to scan for radar and move off them if detected. Maybe the EX7500 is in a better position to pick up radar and causes issus.

have you tried putting the R8500 on the lower 36-48 and then on the higher 149-161? 

You can also set which you want to use for the backhaul as well. If the ex7500 is using the dfs for backhaul and constantly having to switch off because it picks up a signal, it can cause unreliability. 

[Tymok]

Theoretically, devices connected to the extender on dfs channels should also lose signal, this does not hapen with the backhaul runing on lower 5GHz channels (36 - 44)
checked with android WI-FI analizer, looks like the router SSID2 is corrupt, doe some devices linked to it are stable
Tried changing WIFI chanels, no change.

[plemans]

If the EX7500 is picking up the broadcast and not the R8500 it could explain the switch. the devices would switch to the router. 

but it could be a corrupt issue. 

have you tried reisntalling the firmware to the extender, then a factory reset, and reinstall? 

If something is corrupt in the firmware, a reinstall would overwrite it. A factory reset would cover a corrupt setting. 

And if it doesn't work, you could always try downgrading the firmware a version. Maybe something isn't working proper on the firmware you're on. 

[Tymok]

I’ve downgraded the R8500, hard reset etc.
Looks like the radio is corrupt.

After two years my Orbi 5GHz radio broke down, now the R8500. Shame Netgear.