I am not allowed to watch movies or series in 4k UHD

[robertmontblack 0]

When I put a movie or series that is in UHD 4K format, it makes repeated pauses (LAG) and in the playback I cannot even execute the action of overtaking or backing it. I think they should update the webos system of LG TVs. 

[yocker 1552]

A friend has the same issue.
He can fix it by using the compatibility audio track, like for example AC3.