Weird. Mine has been fine (touchwood), from Day 1. They had this nationwide issue for 24 hours or so, but they comped and gave extra voucher for that.
I have the box, but connected to a FHD
TV. I can move it to my 4K TV, but possibly tomorrow or day after.
Let me know a laundry list of things you want to know, and I will see what the box tells me.