Is that fan daisy chained with the other fans? If so, try taking it off the chain and testing. If the issue goes away, the fan might be overloading the ARGB header and you might need to plug it into it’s own ARGB header or consider a dedicated RGB controller (such as a Nollie16).
Sorry for the late reply.
I only had that new fan daisy-chained to the SYS_FAN header for power, not to the ARGB header. I tried completely removing the new fan and reverted to the exact hardware setup I’ve used for over a year, but the flickering is still happening.
Sounds like there’s a conflict of software somewhere then. Have you tried disabling Windows Dynamic Lighting and seeing if your BIOS has any settings there? Triple check for any other software that might also be trying to talk to the fans.
If all else fails, I’d report the bug using the bug icon in the app (upper-right corner) or through this link so that the support team can follow up.