I think it is because Fibe TV box doesn't see HDMI connection after a while, because it expects 60FPS handshake, but it gets 120FPS handshake back and it falls back to whatever it thinks is default resolution.
I am having this exact same issue for a year know, with Samsung QN85B and VIP5662W. Tried multiple certified HDMI 2.1 cables, now on a third box (second one they sent me was refurbished and was switching itself off and was useless). If I read this c...
