I need help with my VLC player

I again switched to a new player. Even after installing the proper codecs some mkv videos were not properly rendering in my VLC player. The issue is, for a small duration ( normally 5 seconds), the video becomes pixelated. Initially, I thought it was the issue with the video, but when I played those videos using a different player (the one that comes default with k-lite codec pack), the video played perfectly. So I switched to this new player- Media player classic( default k-lite codec pack player)