I have Three home broadband and usually have a connection of around 25-30Mbps but have been experiencing a lot of issues streaming content with my NowTV Box. The box is connected via ethernet to a wireless mesh extender, which has a stable connection to my router. What I find is often services don't load up or take a while to get started. Generally Netflix is pretty good, the NowTV app usually works, but takes 5-10 seconds before a stream starts. Disney+ often doesn't work at-all or is patchy at best.
Weirdly, I have none of these issues with my phone, connected to the same extender, with content from any of the above apps loading within seconds. If it wasn't for how reliable things work on my phone on the same network I would be blaming either my wireless network or broadband connection, but I just can't explain the difference in behaviour between phone and streaming box. I have tried the NowTV box connected via Wi-Fi vs Ethernet to see if that's the issue, but that doesn't seem to have made a difference.