Pixilation problem

I have been having major pixilation and tiling issues for a week now.  There has been two technicians out and multiple chats.  They all want me to restart which I’ve done about 10 times now with a cable box swap.  The issue is live tv only, not streaming and it is only on my main box, not the smaller non-recording boxes.  One technician told me it was a maintenance issue dealing with parts that may take two months to resolve.