Quoted from jrcmlc:I was told that the clicking a dozen times++ is "normal" and "won't hurt anything" and Stern does not intend to do fuckall about it. Sigh.
It's not normal. There's an extensive series of posts I did in the Foo thread as I investigated the issue, testing parts, bringing in samples, etc. I finished with a keypost in that thread summarizing the problem's root cause and fix. The problem is low-spec caps from CDE, starting in the 2022 batches. They changed something with the construction of the cap internals, which made them heavier and reduced the quality substantially. The tolerance is 20% on a 10k ohm cap. 2021 and before, most of them tested at about 9500 ohm or above, about 5% reduction from 10k stated value. The 2022 batch has mostly ones that test at 8500 or below (15% up to about 18% off stated value) and that's a real problem because once you're under about 8500, the meanwell power supply thinks there's a short at powerup because the caps aren't charging up as they should. They're slow. The clicking is the power supply protection circuit clicking on and off until the caps finally charge enough. It is ABSOLUTELY not normal. I'd press Stern tech. They know what the problem is. They're likely just trying not to have to replace hundreds or thousands of Power Distribution Boards.
You CAN fix this yourself if you have the soldering skills (these caps are a pain to get out, so if you're a novice, lifting a trace by leaning on it too long is possible, which would make things worse). Based on samples I've brought in, any of the 2021 lots (printed on the cap with week/year format) from CDE will test over 9k, and probably 9.5k. Replacing all three with 2021 lot CDE caps fixes it completely. Costs about $10 plus $8 shipping.