Thank You Hitchhiker for your answer. I don't have an Optimus laptop, but I tried the solution you mentioned. The video is a little bit more smooth, but after 15-20 minutes the video still freezes. This time instead of totally "pausing" the video it plays 3-4 frames in a loop and the audio is still going on. What do you think about it?
As for the TV it's LG 65UK6400PLF, so it should be compliant.
I checked the specs for your TV and it has three HDMI 2.0 ports which is the latest HDMI spec. More details on that score
here
However, your laptop which dates from 2015 will likely have the HDMI 1.4 specification. That's not such a big problem since HDMI 2.0 is backwards compatible with previous version. But it does mean that data transfer rates will be slowed down to the 1.4 spec even if you use an HDMI 2.0 cable. More info on both specifications
here
You could check the laptop manufacturer's site to see if there's a firmware upgrade available which might help otherwise try a different output module in vlc settings (Ctrl + P to open and then click Video button and select from there).