In my network, with 2 Deco M9 Plus (one is the main Deco, and the gateway) and 3 Deco P7, i have noticed that QoS really doesn't works very well! I setted a customised mode, with download priority at...

As shown in the image, the red deco P7 sometimes, instead of connecting to the Deco P9, it connects to the other P7 that is further away! The black P7 is the "main" deco, the internet gateway, and is...