@Elaine8 several things can increase latency the most common is wifi which you are avoiding by using ethernet cables as long as these are direct from the console to the hub.
Second common cause is the Sky hub being busy if you have several simultaenous users such as your son gaming and multiple other family users streaming video the gaming data can get held up while the router is dealing with other traffic in larger households. If that sounds likely then you may need a router thst supports QOS which prioritises gaming traffic these are not cheap but with Sky Ultrafast services Asus's routers seem to work well.
Third cause is congestion at the server which most gaming companies suffer from after a major release for example we get a lot of "latency" issues each year around early October when dug down it is with EA games annual football release. Check online and suddenly every isp seems affected oddly EA games blame everyone else. 😉
It is possible there is an issue within Sky's network but these are far rarer than most people imagine users can check if their line is slow by setting up a Broadband Quality Monitor here https://www.thinkbroadband.com/broadband/monitoring/quality use the IP4 address for the monitor. This gives a check on round trip time from a server near the main London internet exchange and your hub it will show up any issues within the Sky backhaul routing and if the hub is getting too busy.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
