I personally use have two of these bad boys, with substantial hours on them controlled through an AC Infinity controller. I have never experienced this issue. I actually am infatuated with my S33s, I crank DLI out with a pair in a 2x4.
I have had similar experiences with Vivosun controllers over time with internal circuits failing (like testing the device and cords they're fine) where a factory reset doesn't work. I imagine the power supply via USBC (and the current that implies) does not mesh well with the low-current control signals over time, or at least the internal circuits.
UPDATE US. I tore them a new one over a shoddy stitching job on a pro-level tent, they reshipped me one quickly. Each AC Infinity item should have a quality control number on it so they can dial in the issue and confirm you deserve a replacement. I love their innovation, and don't mind paying a premium for quality assurances, but this ain't it. Controllers are very much the future of the industry and this is terrible advertising until resolved.
@ACINFINITYINC