After switching dimensions beam former cause visual glitches to appear. Breaking and replacing the beam former fixes it until switching dimensions again.

Mod Version: 1.6.4 (also tested and already bugged for 1.6.1)
Modpack: MeatballCraft

Glitched diamond chest + more in background (mana spreader and other diamond chests)

(using beacon rendering, from logs:)
[01:45:54] [Client thread/WARN] [NAE2]: No GregTech bloom API found. Beam formers will fall back to beacon rendering.