My tv is an lg 4k and there's no lag in game mode. Make sure motion plus is off but I don't think it would be on in game mode. Have you calibrated your joycons in settings. Don't know if that makes a difference but could
For the ones having a Samsung ks9000. Which are the best mode and settings for the Switch? I just bought the TV a couple of days ago, so any tips are more than welcome.
It works perfectly on my samsung 4k smart tv. Try unplugging everything from your wall socket except your switch and tv. Th switch is stingy when it doesnt get the power it wants. Mine wont even turn up on the tv at all sometimes if it doesnt get enough power.
Its your tv that sucks. Most tvs are not made for gaming and has extreme input lag >50ms , even in game mode my samsung tv is not great, i feel it. however try an connect your switch to a pc monitor and see.. i think the switch is Not the problem but the monitor your are using..
Try to manual update to newest firmware, and try both turn OFF HDR, and try the HDR GAME mode also... if you dont have the hdr game , then you have old firmware , and need to download and put on usb stick to manual update
You probably dont have game mode on man. And big 4k TVs have VERY bad input lag especially not in game mode. I have a 28" 4k monitor with a 2ms input lag!