Since the release of 1.6.0/1.1.0 firmware versions, A new feature has been added that users will get a notification on the Deco APP when the Internet negotiation speed between Deco and modem is lower than expected. For example, for gigabit models, like Deco M5/M9 Plus, you could get an error message when the internet negotiation speed is lower than 100m/s. While on Multi-gigabit models, like Deco X90 and Deco X50-POE with 2.5G Ports, the detection mechanism would be a little different.
 
 

Here are some cases we have received recently:
 

Case One: For Gigabit models, like Deco M5/M9 Plus.
 

Since this new Ethernet link speed detection feature was added since 1.6.0, some users might think it was brought by the firmware upgrade but actually it wasn't related to any firmware upgrade.
 

So if you happened to get a notification on the Deco APP, the following suggestions would help:

• Remove Deco from the modem and connect a laptop via the same cable to the ISP modem to make sure the laptop can still stably get more than 100m/s.
• Restart the main Deco once.

If the speed could be restored every time after a fresh restart and dropped down again a few hours later, please replace a new Ethernet cable and change a different Deco as the main Deco.>>How to Set up the Satellite Deco or a new Deco to be the Main Deco

•  If Restart did not make any difference, please hold the reset pinhole for 1s and set it again from scratches.

Case Two: For Multi-gigabit models, like Deco X90/X5700/X50-POE etc.
 

For Deco with 2.5G ports, when the ISP modem is connected to its 2.5G port, the expected negotiation speed is supposed to be 2.5G. So when the internet bandwidth is only 1G/s, the 2.5G port on Deco could only get 1G speed negotiation which is less than what it is capable of. You could get a notification of Abnormal WNA speed but It actually does not affect the final internet bandwidth since the total internet bandwidth is only 1G. 

It could be temporarily resolved by connecting the ISP modem to the 1G port of the main Deco.
This issue has been located and will be improved along with the firmware update of Deco.

However, for Multi-gigabit models, if the actual speed was affected and lowered than 1G when the APP reported Abnormal speed, please also refer to the suggestions in Case One as well.

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