@donnas18 assume you are trying tobstream video which is whst is buffering. This is almost certainly due to insufficent signal strength and interference probsbly from your neighbours' networks. To stream video you need both sufficent bandwidth but just as important a signal with low jitter (tge measure of stability).
Ideally you would use Ethernet cables if that is practical. If the issue is confined to one room some way from the hub then powerline networking kit can help,as those uses the main's wiring to carry the data. Alternstively you could invest in a whole home WiFi solution. Sky sell an add-on called WiFi Max which can comecwith up to 3 extenders if you prefer to pay a monthly charge rather than buying your own kit.
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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
