@Aubs2 & @Shelby8 most common cause is poir wifi signal at the TV or streaming device. If you have the Netflix app run the Network test innthe Get Help menu as thatvwill tell you the bandwidth the devicecis getting you need a steady 30Mb/s for UHD streaming.
In many homes the Sky hub cannot deliver that in every room so you need more kit. However before spending money make sure your hub andctgecstreaming devicecis in the best position which is out in the open and if using a device like a Firestick or Sky's Stream puck not hudden behind the TV. As thhey block a lot ofvthe signal. Sky will sell yountheir Sky WiFi Max bundle see https://www.sky.com/help/articles/sky-wifi-max which can providevupm3 extenders or you can buybyour own kit. Other isps sell similar systems as their free hubs are not significantly more powerful due to regulstions limiting output.
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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
