@Darran23 like the idea of Supernatural 500 but I am assuming you mean Full Fibre 500 that is the speed to your hub which is accessible by your devices over a fast network link likeca Gigabit Ethernet cable. Devices connected by WiFi msy get slower speeds due to the WiFi signal being affected by the layout and type of construction of your home.
Assuming your hub is out in the open on a surface you should get close to 500Mb/s in the same room. However by the time the signal has passed through two or three solid walls speeds will have dropped. 65 to 80 Mb/s is amole to stream video actually its around double the bandwidth any streaming can use but if your wifi signal is poor it is likely to be easily disrupted by interference which would explain the buffering. You need to consider getting extra wifi equipment. Sky can sell you their WiFi} Max bundlecwhich gurantees 25Mb/s in every room and can supply up to 3 pod extenders or you can simply buy your own wifi kit and use that.
You reported 65MB/s which is the unit services like Stream report which mega Bytes per second while network speeds are usually measured in megabits per second given there are 8bits in a byte 65MB/s is 520Mb/s which is slightly more than the maximum your connection can deliver so I assume you misquoted the unit.
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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
