@TP-Link So same problem for me as well.

Got 4 Deco M9 Plus backhauled via ethernet to a TP-Link Switch.

Get the message as described by all here consistently on the app.

The app says my firmware is up to date.

Got about 20 devices on the network.

Major symptom is that my wife's VPN to her office keeps on getting dropped or hung up. She ends up going to the basement and rebooting the "router" every 3 hours or so. She notices as she does big file transfers all the time.

  @TP-Link  deco e4 v1.  1.5.4

Firmware.

same

problem . Near me a lot of wifi network  5-6 5ghz , and  12 2.4ghz. The deco use only 38,42,44 channel.  Why don't use 136-152 channel?

  @TP-Link  How do I install the Beta FW?

  @TP-Link can this beta update be applied to Deco M9? Don't see it listed.

TP-Link wrote

This Article Applies to: 
Deco with 1.5.x and higher firmware versions


Issue Description/Phenomenon:
Some customers may report that the Network Optimization feature on their Deco app always displays the network needs to be optimized even though the last optimization result was perfect minutes ago. 



Cause of the Problem:
Network optimization would help Deco scan the available Wi-Fi channels and select the most empty channel automatically. After the first optimization, all the Deco nodes and all the client devices connected to the Deco network will switch to the new channel.  While With all the Deco nodes and client devices attaching to this channel, it would be crowded again so the Deco app will show you the network needs to be optimized again.

Besides, whether the Wi-Fi channel is congested also depends on the network environment. For example, if you are streaming an HD video, or downloading a large file, the Wi-Fi channel will become more congested than the situation that there are no active devices in the network. 


Solution:
Normally Network optimization would not cause any network issue and there is no need to scan the network frequently. However, if the Wi-Fi channel is changed too frequently, it may cause an unstable issue on the client devices, some devices may disconnect from the network and reconnect. We work actively to optimize this feature and provide beta firmware for some models here on the community, you could install the beta firmware to monitor the performance:
Deco M4-20220714
Deco M5-20220701
Deco X25-V2-1.1.3 build 20220628
Deco X20-V2-1.1.3 build 20220628
Deco W3600-V2-1.1.3 build 20220628

Note:
1. Please check the device label to verify the country code and hardware version of your device first, and choose the correct file to download and install.
2. Be sure you have read the Terms and Conditions for TP-Link Beta Firmware before proceeding!


If your model is not getting a beta firmware, but you experience some issues like slow speed, internet stability, or some devices can no longer connect to the Deco network after the optimization proceeds, please feel free to comment below and be sure to provide the following information:
1. The model of the Deco device
2. The number of the Deco nodes
3. The number of connected client devices
4. Detailed issue description

 

 

-------------------------------------------------
Have other off-topic issues to report? 
Welcome to > Start a New Thread < and elaborate on the issue for assistance.

  @TP-Link 

Trying new beta firmware with no positive changes:

1. The model of the Deco device: Deco X20 V2
2. The number of the Deco nodes: 2 in AP-Mode
3. The number of connected client devices: 20 - 25
4. Detailed issue description:

5 GHz is always on channel 36 even after restart or after network optimization. Channel gets not changed even there are no devices on channel 44 and higher.

Also there are two hidden SSID, one on each of the Deco nodes. I assume these are normally used for WiFi backhaul, but I am using Ethernet Backhaul. And as these two hidden SSID also are on channel 36 they do interfere with the client SSID. 

a) the two hidden SSID (WiFi Backhaul) should not use same channel as client SSID

b) if ethernet backhaul is used, WiFi backhaul should be deactivated

c) if WiFi backhaul is deactivated, the senders could help to strengthen and bundle with the client SSID and accept client connections (then on same channel)

d) channel should swith to a channel with less interference automatically 

I upodated the Beta FW - it is a bit better but still sometoimes congested and I have to optimze manually.