What you see as sampling settings is what is happening in your mooshimeter. So 32smpl/125Hz would be just that, nothing to do with 4000.
With those setting, every one value, for log or user interface, is generated by taking samples at 1/125 s intervals, 32 times in a row and then averaging (or some RMS stuff for AC) those. That would take some time, roughly 32/125 s + ~0.1 s for processing. And then, repeat from the start. If you set logging intervals to “no wait”, those settings would give you roughly 3 values per second.
As you set higher samplerates, you quickly realize that you can’t get past ~10 log-lines per second, as processing still takes same time every round. In some cases, you might want to set samplesize to bigger value, for more stable results. That again would mean it takes more time to get those samples and rate that you get new values would drop. Max samplesize times lowest samplerate takes over 2 seconds for a round. You just need to know what you are trying to measure and what is it that you want to see from your data. If there is time to spare before next logging interval, mooshimeter goes to sleep to save power. In that last example, nowait and 1s interval settings would still both give you only one log line every 2 seconds.
As always, i’m afraid to read the question again, probably wondered quite far from what i should have written :D