In my normal world (private) I have no issue with the following problem. I tested that fact since I made the video link you'll see below.

In realms, and this has been going on for over a month (since I started the realm) when I ride a mine cart, or any of my friends do, there is an audio glitch which propagates getting increasingly worse until the smooth motion of the game stutters.

Then the audio noise resets and starts again.

See following link I editing from a life stream showing the issue.
https://youtu.be/t70u0asPorU