I have a mesh network,Deco x50 ( AP mode) set up connected to my sky router (sr203) via ethernet cable. Along with FTTP with sky fibre 100. Wifi is turned off on the router and I have turned off dhcp beam forming etc on deco. I have 3 deco nodes with no scope for ethernet backhaul.
 

I have a sky stream puck connected via ethernet cable to my hub (sr203). The hub is connected to openreach ONT. However I am experiencing slow speeds and apps either failing to load or being extremely sluggish such as netflix etc. I am experiencing similar issues with devices connected to my deco network, apps being sluggish, images failing to load in the likes of instagram.

I have done numerous speed tests through both the netflix app (110mb/s) and also through my phone which is giving similar speeds so speed to the premises isnt an issue.

Does anyone have any ideas or fixes?