You can't stop live tv
You can't remove individual channels Its best to create a favourites list
For favourites hit yellow button
Lots of guides https://www.youtube.com/c/BuzzTVGlobal/videos
Do you also use the same model router? Wired the same?
Have you ever taken your box to you bil place to see if issue follows the box?
As you said his works fine so its obviously not a worst piece of tech!