[Bibio]

now got it playing for days or no dropped/repeated frames with 4k hdr, bluray and dvd :-)

Warner306 is correct in saying, dont touch the reset gpu button while configuring custom modes.

i also think that changing modes while in the nvidia cp helped as well, also changing to rgb, 12bit and full helped before configuring the custom mode.

also got rid of the sunburnt skin tones by changing the LG tv colour gamut to auto instead of wide, extended.