It seems VLC is tailored for HD resolution - my laptop has 4K screen and VLC seems to struggle with 4K and can't play video at all for 6k or 8k even though potplayer works fine for those resolutions. There is GPU that can handle higher resolutions and plays in several other protools (daVinci, etc) and also VirtualDub 64bit.
Seems not to matter bitrate or codec.
As mentioned in other post about sound sync - system is latest windows 10 Pro, latest VLC, 48GB memory, SSD and nvme scratch Disk, lots of free space, NVIDIA P1000 GPU and 6 core i7.
Thanks