@terziyski Eventually i purchased another AX6000 and sent back under warranty the C5400X. Wouldn't risk keeping it and possibly have other issues out of warranty. Thank you for your help.

@Kevin_Z Configuration wise I haven't changed anything. The router is still in access point mode. Only thing I changed was the erthenet cable, instead of the WAN port I put it in a LAN port.

@Kevin_Z The Archer AX11000 turned off and never turned back on out of the blue. As for your suggestion with regards to Archer C5400X, i have connected the cable coming from the AX6000 (LAN port) to...

Same issue for me as described here: https://community.tp-link.com/en/home/forum/topic/548132?page=1 Archer C5400X connected to AX6000, both on latest firmware, started getting capped at 100Mbps....

@terziyski It's already on the latest firmware build. Will return it under warranty then. Thank you for your assistance. It's a shame really, 6 months ago my AX11000 stopped working and know this....

@TheFaLLeN I have spent the last 2 hours trying several scenarios : Tried 4 different CAT 5E / 6 cables Connected the C5400X directly on the AX6000 (they are located on different floors) Connected...