Asus AI Mesh Zenwifi xt8, missing connection on LAN

[rt2016]

Hi all,

I do have a question around connectivity.

Having the following setup:

Asus Router RT-AC88U (The router is placed on the loft.)

Feeding the cable's via Telegärtner MPD cat6a

Feeding 3 Zenwifi xt Stations as AI-Mesh.

All do have the newest software installed.

The ZENWIFIF XT8 stations are connected via LAN.

But from time to time the station starts getting into blue light around 1 or 2 minutes and then turn back again to normal.

The length of the cables is around 14 Meters from the Telegärtner device.

Do I need a switch to get a 100% stability?

best regards
rt2016