Suddenly got instant bufring issues

I use nvidia shield and kodi to stream from mycloud. Everything connected via CAT6-cables. Had this setup for years and never seen a bufring until a couple of weeks ago, and now it’s just a pain in the ass. Bufring at least 30-40 times during a regular 90 min movie, and it doesen’t matter if the the movie is 4K or HD or whatever.

MyCloud seems fine, newest software and diagnosed OK. So what might this be about?