@LelWatson you nedd a string stable wifi signal to stream video or you get buffering. Improving the wifi in the room you watch TV should sort the issue or better connect the TV by an Ethernet cable to your Sky hub.
Poor WiFi coverage is probably the most common question we get in the forum. In many homes a single Sky hub cannot provide a usable wifi signal in every room due to the layout and type of construction of the property especially in older homes. Assuming the hub is in the best possible position which is out in the open on a surfsce then the only answer is additional wifi sources.
Your choice.is to either buy Sky's add-on WiFi Max bundle which can supply up to 3 extenders see https://www.sky.com/help/articles/sky-wifi-max or buy your own wifi system and use that instead of the Sky hub's WiFi.
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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
