Random devices connects to the SSID but have not network connection or internet access

[IvanMorales89]

Hello team!!

We are facing an issue in our Ruckus Unleashed environment.
There are 15 APs in total, APs are R610 (4), R510 (2) and R320 (9)
Software version: 200.15.6.112.54 (We upgraded this recently, trying to solve the issue)

This started about 1 month ago, the issue is the following, devices connect to one of the wireless networks, they get IP address and all the network parameters from DHCP without errors, but they are not able to access Internet or anything, for example, I ping something in the local network wich has the ping enabled, and we are not receiving any reply, for example when I ping the local gateway.
This happens some days, sometimes, randomly.
The issue seems to happen more often in some SSIDs than others, however all APs have all SSIDs
Also, we found recently that too much devices are with signal "poor", about 20% of devices with poor signal. This is new too, but we could not identify if the issue happens in devices with poor signal or not.
We checked all wired connections and settings and this is ok, even this are the same settings that previously works (Before this issue started)
In same notebooks, when they are connected with patchcords to the network, they work without problems

We don't know how Unleashed decide to which AP connect each client, is there some documentation with this information?
Any idea will be appreciated!

Thanks in advance.
Regards,
Iván