I've tested a load of lines and my own findings seems to me that each server seems to have issues with certain channels and how fast they clear, for example on my current line, ginx esports tv is really poor and is so bad I dont even bother watching it and it glitches and stops like crazy, thankfully its the only channel I'm aware of that runs so poor on my line and the remaining important ones are working great.
I notice on some lines that channels that are free to air by other means seem to be the ones which have the most issues clearing on cable, but I tend to watch those on satellite as got a combo box so not too much of a issue, I've read about cache servers and main servers, and think its the cache servers that mostly do this, how you know if someone has a main server or not I have no idea as no provider tells the truth when you ask them about channel problems.