At every version MT higer than 6.20 I have many clients disconnects from AP. The last good version for radio AP and clients (Nstreme) is 6.20 for me. Could You confirm that problem? Just try to MAC-telnet to any CPE connected to MT AP - from that AP. Some of clients works good, but some - disconnects frequently at that operation or at high traffic. Downgrade to 6.20 - no problem with radio disconnets. Could You check and confirm - please?

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What is the signal on those clients? What is the disconnect reason in the log?

Signals about: from -54 to -66
Logs:
At the AP: disconnected, extensive data loss
At the CPE: lost connection, not polled for too long
I am using Nstreme and polling. At version 6.20 - there are no problems. EVERY version after 6.20 - that problem occurs. Disconnection is about 1-2 seconds, but - THERE IS.

Switch to Nv2 and you will not see "Not pooled for too long"

Switch to Nv2 and you will not see "Not pooled for too long"

It's NOT solution. I don't want to have a much more latencies, like NV2 introduces.
Besides, Nstreme and polling is working good, almost at all versions max to 6.20 .
So - there is something wrong with Nstreme and polling from 6.21.