Strange, I can watch most for hours without freezing or playback issues. I use an M3U list, with Kodi 16 and playlist loader on iks66. I have tried other methods, PVR Stalker, xtreme codes, they all work fine.
Now I'm usually watching just news channels and a couple movie channels. They time out after a couple hours, but I can live with that. For me, this has been the best the service has been for over a yr. I even export my M3U list to my phone and playback channels over cellular, works fine.
And believe me, I've been critical of the service for some time.