Why would only certain channels have problems with buffering? I can watch some channels fine and there are a couple (of course my favorite) that buffer all the time. I've tried two different iptv providers, I've ran my ethernet straight to my firestick, I delete caches, etc and nothing works.
Well, odds are you just bought from another reseller which very possibly is selling the same original source. There are only a few original source (original source is the people actually capturing the streams) providers and a ton of resellers which use their own branding but sell the same service. If the problem is at the source then switching resellers that happens to sell from the same source does not fix the problem. Also, as someone else already stated, this is cheap bootleg illegitimate TV, it's just a few people using some cheap ass hardware capturing streams with no backend infrastructure in place except for a few servers they usually lease in a datacenter. Not a multi-billion dollar company with a ton of people and hardware to keep the signal as close to perfect as possible.
I just bought a months worth of service from another provider to see if that was the issue and I still have the problem. The main channel that buffers is Nat. Geo. Wild
There are a lot of providers that over sell their service and have to many subscribers, you will get buffering when a lot of subscribers are all trying to watch the same show.
Get hold the provider
IPTV seems to make my firestick very hot which in turn makes it buffer more- to combat this I plugged a usb fan next to it to keep it cool. I’ve seen a vast improvement by doing this. I’m afraid with IPTV it’s a process of elimination. Hope this helps.
Have you tried using a VPN?
HD vs SD channels? HD channels tend to buffer more.
It's a provider issue - but it's also cheap bootleg TV, so.....