Hi,

I recently updated my firmware from Deco M5(EU)_V1_201022 to Deco M5(EU)_V1_1.5.3_20210203. It didn't show up in the app (App just said No updates available for your device), so i just downloaded from the website and manually uploaded the file through the 192.168.0.1 GUI.

After updating successfully, the unit was restarted and immediately i noticed an issue :- most websites weren't loading properly. Some websites would just partially load, including google.com, and others would be stuck with a loading bar until refreshed multiple times. Some devices like FireTV would show only half the contents or take an absurdly long time to load. Similar issues noted on the iPad, MacBook Air, Windows PC & iPhone. Unit was NOT reset and NO Changes were made to the Deco settings.

I rebooted the units, added/removed the WiFi networks from my devices, disabled/changed iPv6 settings, and ran Network Optimization tool, which by the way was also a new observance as I was more frequently than before getting Network Congested messages. 

Honestly, worst decision I've made. Its just not diagnosable. There nothing in the Sys logs or any info from my devices that I can use to understand why the Deco is behaving so weird.