Buffering /lagging happens to prevent the video from stopping to load, your networked component "buffers" the video. That is, it streams the video ahead of what you are watching so it plays continuously.
When the video catches up to the point where the file has been streaming, there might be a delay. This results in "buffering" and a pause in the movie playback. If the streaming video reaches the point where it has to wait until more information is available, it will pause, and you'll see a rotating arrow or spinning circle on your TV screen. Once the video stream catches up, it plays again.
Lagging content is most probably triggered by network condition so kindly check your internet signal strength by disconnecting other devices and play content continuously until the network signal strength picks up for the content output quality.
One can also test internet speed can be done by VOD Apps like YouTube & Netflix apps have in build internet speed test feature will provide the full internet signal strength speed details.
Repeated buffering can result from a technical problem with the content provider or your internet service provider (ISP), but it also can occur when too many devices are using your internet connection at the same time. Most of the time, issue is because of the internet speed.