Thank you for reaching out, have you tried a different HDMI cable to see if the issue still occurs?
I know in the menu that 720p is as high as it goes but once you go in-game it switches to 1080p as long as the game supports it. Since you did say that 1080p works with your Xbox have you had a chance to contact Nintendo?
Same TV Samsung UHD Q70 7 series. Same flickering, back and forth of recognizing and not recognizing the source (Switch)
I found a solution. Turn the TV Setting in the Switch menu from automatic to Limited Range. For whatever reason Limited range works.
This worked for me too! After buying a 55" 4k UHD tv from Samsung last year this not recognising the Switch on the tv and constant black screen flickers on/off when using it annoyed me.
I advised Samsung and they sent a tv repair guy out who said it must be thr Switch as my Xbox One X and Playstation had no problem on the tv. But the switch works fine on my other tv's?? Hopefully an update releases to identify it better as the first time it was connected it seemed to, came up with the logo and everything in Smart view.
THANKS! FOR THE RGB RESTRICT MOVE. 😎
I have the same issue, I bought a Samsung Q70R and I am not able to use my Nintendo Switch on 1080, I tried to connect to different HDMI ports and changed the HDMI cable and I am still with the same problem, this is a little bit disappointing, with Xbox one x I don't have any issue.