I did a network optimalisation with the app and then the Deco goes back to the previous setup. So for as long as you don't do that, it will connect to the nearest one.

In the end I think i'm going to follow the advice and put a gigabit cable to this room so that i can backhaul the deco. Eventually I will need to do that anyway, so might as well do it now.

@TP-Link hello, I'm having the same problem..I have 5 deco M5 in my duplex and the signal strength for everything deco is extremely weak. May I use the beta firmware?

thanks

@Semibalbi 

Hi, here it is:

https://community.tp-link.com/en/home/forum/topic/173748?replyId=598954

@TP-Link i have 3pcs of m5...just realized the second floor m5 was not strong enough signal... 

1 on 1st floor 2 on 2second floor...on second floor 1 signal is ok 1 is not ok and both is just nearby

@TP-Link 

When are you rolling out the official firmware update?
The beta one already has several months.

@TP-Link 

Do you have a firmware to have the signal source selectable? Some of the slave nodes are not connecting to the closer nodes and is connecting to the one furthest /weakest. 

@TP-Link 

Thanks for you helpful reply, but I am facing the same issue with Deco x20

I'm Facing the same problem...... i Have 5 Decos 2xM5 & 3xM4R

please release update asap..

@TP-Link hi, is there one for the m9 plus as well?

Please TP-LINK, hurry up and release the firmware for the M5, allowing you to choose the signal source.  I have four Units and they either all connect to the main unit or three to the main and one out on its own which connects randomly to one of the other three, normally the weakest one! 

What is taking so long, seriously thinking of returning them as not fit for purpose.