Lines on screen - help!

[standing and walking]

Hey -

Googled but nothing seems to match my situation. When I play videos on my Macbook (OS Sierra 10.12.6) I get these flashing little lines all over the screen. I took a still shot but they flicker the entire time a video is playing. When I play via the renderer they're not there but anytime I'm playing video, even with an HDMI out, it's got these little lines all over the screen. I've tried 2.x and 3.x versions of VLC and have the same problem everywhere. I've never had this on any of my other Macs. Does anyone know a solution short of installing a new OS? There's some software I use that I prefer to not pay to upgrade that works perfectly well on this OS, and every earlier OS has played VLC videos just fine. This is a problem regardless of the media type - mp4, mkv, doesn't matter.

Screenshot here: https://imgur.com/NuJjpat

Thanks!

[ePirat]

If using a recent version of VLC (3.0.10) you can try to set the Video Output to the Core Animation OpenGL Layer one and see if that fixes the problem.