New to iptv so i am not sure if normal. Yesterday during the day the streams all work almost perfectly but then during the evening most streams had some kind of buffering going on. I am not sure if normal or if the hardware I am using is causing it roku express . 30mbps internet speed.
Are you able to try it using something else like vlc player on your laptop? Roku is not the best for iptv as the platform is limited. I would be curious to see if it improves on something else.