Problems with ConbeeII and deCONZ

Setup:
NUC with proxmox and home assistant, installed yesterday.
ConbeeII dongle with 5m extension cable.
4 aqara temperature sensors, 2 zigbee bulbs

Problem:
3 sensors work good, the 4th can’t connect.
Bulbs: no problems either
When I open deConz, mostly I can’t connect. When it works it’s only for a few seconds, then lost connection.

I hadn’t problems with my raspberry pi.

I’m stuck, some help? :slight_smile: