Thanks for repeating this test. Going back and looking at the first time I ran it, they both dropped to around 1.5. So not exactly 0. So far, every time I have seen it glitch, it is always towards a lower value.
I'm surprised they wouldn't have caught something like this but then again, that counter spec doesn't give me any comfort.
With them recently sending that one reviewer a meter, they may be able to provide them feedback.
Chance92 and others would have to decide if its going to be a problem for them. I can imagine if you are running a long term experiment and the signal is not stable as you expect, then your spending time trying to track down if it's something on your end or the equipment, that will get old fast. I guess, just something else to be aware of if you buy one of these meters.