Is it viable to run an Ethernet cable from your router to your Stream box? If the problem is WiFi based then that would sort it out with the least fuss.
It should also be noted that Sky can use a lot more bandwidth than apps on iPad etc. so it's possible your internet is struggling with the demand of Sky streaming TV (even compared to Sky Go app). You can do a speed test within the Netflix app on Sky and if you can reply with your speed result we might be able to give a bit more tailored advice. The speed test is buried in a help option on Netflix's menu.
Another consideration is placement. Being portable, your iPad might have free reign with uninterrupted signal but your stream box might be up against a wall, hidden behind a metal TV etc. which can lower the signal quality.
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Sky Stream customer. Past user of Sky Digital, Sky+, Sky+ HD and Sky Q. 3x pucks. Main TV is an LG OLED with Sonos Beam.
