I bought a decent 4k monitor to go with my 4k media box, and the required 4k cable, but wouldnt play because 'for your safety, blocked because not a TV' or some such nonsense, think it was HDCP? Annoying enough for me to cancel 4k paid tv, plus they were busy agressively reducing the broadcast bitrate. Also ended up with a load of bluray 4k discs I cant use, and they wonder why people download stuff.