@JJMcevoy by far the most common reason for Stream buffering is a poor data connection between your Sky hub and the puck. Improving wifi in your home or using ethernet cables should solve the issue. To help ensure both the hub and the puck are out in the open on a surface so they are above obstructions like radiators.
Beyond that you are into needing additional wifi sources as the layout and type of construction of your home means a single hub cannot give sufficent signal to the puck. Sky will sell you an add on called WiFi Max which can supply up to 3 extenders see https://www.sky.com/help/articles/sky-wifi-max or you can do as I do myself switch off the hub's wifi and use a third party whole home wifi set up which means my own pucks are 100% stable.
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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
