Just to close the loop here in case it may be helpful to others:
My faulty Mikro, which had 3 pads that consistently stuck or stopped triggering, was returned and refunded by the retailer.
It was sticking and failing to trigger whether pad sensitivity was set to 0 or 100 and settings in between. Clearly due to faulty pad hardware.
I bought a replacement and it is absolutely perfect and I LOVE it. I’ve been whacking away at that thing for hours over the last few days and the triggering is entirely consistent, and the sensitivity adjustments are incredibly accurate and effective. I set sensitivity to about 80 or so and, with some velocity curve adjustments in the kits to account for imbalance in my finger strength (my right ring finger is weak on the side stick, eg, and my right index was hot and sometimes bounced, creating a second hit before tweaking the velocity curve), I’m totally sold on this controller.