Hello Jules2420,
I can imagine it's incredibly frustrating to have this happen. I understand equipment has been replaced and the issue remains. With the picture still breaking up, we'll need to help reserve a return visit to get traction on where the issue is caused. If the picture quality issue is present at random, then this can possibly make it a bit difficult to track a solution if it's not happening during the appointment. You may email cox.help@cox.com with your complete address and name, and we can look into this for you. If a service visit is needed, we may recommend a date and time-frame that works best for you as well as a time-frame you find the issue is most present.
Dustin
Cox Forum Support Moderator