@Helga I have set of Deco M9 Plus for about two years, and it is stable. Let's find reasons your Deco M9 Plus set is not running well with your devices. I have questions for you: 1. You listed...

@Schueler Schueler wrote @Heidi_Alp thanks, mist this one... will check whats new. But I have to install APP 3.0 as well... which is only in the store for Apple users, not Andriod. I preferable don't...

@Amano7 That makes sense. If you are concerned with future proofing, and plan to upgrade Internet connection to more than gigabit, check prices for Deco models with 2.5Gbps and 10Gbps Ethernet ports....

@tecoholic If suspect is Ethernet cable, the Master Plan would be to connect either one or both Deco not through that cable directly. This might solve the problem by having device other than Deco...

@Gurry TP-Link released beta firmware for Deco M4(V4) that allows to manually select where Satellite Deco should connect: https://community.tp-link.com/en/home/forum/topic/581554 You only need to...

@Amano7 If you want tri-band, you can also choose from Deco X68 and X90. They are tri-band and based on same WiFi6 technology as X60, so if you are OK with X60 performance - Deco X68 and especially...