Swix has a magnetic stirrer/hotplate combo (and it rocks!). Anyway, sometimes when the volume of solution is low, the spinner is too fast (on the lowest setting).
SO, Swix observed that when you crank the spin speed UP in speed, the magnet looses its 'grip' on the spinner bar. This results in the spin bar agitating (which is good) and making about 1 revolution per 5 secs or so. Other agitation/spin combos can bee achieved as well (OK, I WAS BORED!!)
So in conclusion, don't assume the lowest speed setting is the slowest. Experiment with different spin bars, solution volumes and spin speeds. Also, putting the spin bar off axis with the magnet can create some nice 'swirl' actions. All these motions can bee maintained for hours unless disturbed.