Hiyas, bit of a weird one with my RE505x (Uk version V1 and the latest firmware) When the 5ghz band is connected from the router to the extender at all it stops Wi-Fi working altogether. All lights on and showing 5ghz and 2.4 connected and shows connected in both the app and the the web link but nope no joy getting internet and connected to either the 2.4 or 5ghz extender SSID (both individually named)

The only way I can get it to work is by going into the high speed settings and selecting 2.4ghz from router to extender and 5ghz from extender to device. Anytime the extender receives a 5ghz signal it just stops working even though everything reports as fine. Reset and rebooted both the extender and router (Virginmedia Hub 5 Wifi 6 capable) quite a few times but nope nothing seems to work.

I've changed the 5ghz to channel 36, 40, 44 and 48 through the router one at a time to see if it was causing a problem. Both bands are named separately (both router bands and extender SSIDs and correctly setup and the extender is within range. Does it seem like the extender itself is knackered? It seems like as soon as the extender receives 5ghz from the router it throws a wobbly but works faultlessly if I completely disable the 5Ghz from router to extender by disabling the auto high speed and manually selecting the 2.4 from router to 5ghz to device. I'm more than likely missing something so obvious though. 

No biggie as it works just wondering if it's time to upgrade.