Is this an ISP Issue? I bought a Deco m5 mesh system and it has helped immensely. The overwhelming majority of channels I've watched are great however there's a handful of channels that are unwatchable. Other times, I'll notice it buffer a handful of times during a game or something.
I just watch iptv on my phone and TV at the same time. My phone data didn't buffer but the WIFI Did. I have 100 MBPS internet and it's not overloaded at all. I have my Smart TV plugged in to the Deco m5. I'm unable to connect straight to my router but I'm still getting around 65 mbps with this setup.
Your WiFi is blocking it , get a vpn