I have a row of WS2812B on my PCB. I have 3 identical PCBs, and on 1 board the WS2812Bs are "twitching". They are showing colors just fine, but RGBs are flickering / twitching repeatedly. It happens very quickly but nonetheless very visible. Has anyone seen this issue in the past?
I figured out the solution. It has nothing to do with electrically. My contract manufacturer flashed the MCU via ISP and in the process they changed the fuse bits. I have since reset the fuse bits to the default and it no longer exhibits this issue.
Default fuse bits: L 0x5E H 0x99 E 0xF3 LB 0x2C
This is quite puzzling nonetheless. I will update once I figure out the exact fuse bit that resulted in the random flicker.