@David-TP 
I am having a lot of problems, my wifi always select a bad channel. When I run network optimization show this:

But if I run the teste on lab, the result shows a lot of interference:

 

The network optimizer is not able to select the best channel, and as a result I always have problems with slow wireless. My M4R already has updated firmware. Is there any way to solve this problem?

  @franklinmg Sadly none that I know of.

  @Hama Honestly after seeing all this, we are taking our 3 deco's back tomorrow and just investing in Unifi.. These TP-Link people are absolute morons when it comes to actual products in general. These Deco's couldn't even get out of their own way here for our home... we only have a 1500sqft home..