I am experiencing every time I turn on xfinity stream on my Samsung Closed Caption is on & no one at Comcast seems to know why, please help

I am experiencing every time I turn on xfinity stream on my  Samsung smart TV Closed Caption is on & no one at Comcast seems to know why, please help. 

I also get buffing and lagging at night at around 8 pm when I am watching xfinity stream on my Samsung smart TV. 

These issue have had no resolution through Comcast and I have had xfinity stream for 2 years and has had buffing and lagging issues ever since.