According to my testing, this only happens when cubes are dropped onto a fizzler (which must be deactivated separately to get the cube), but apparently when cubes are dropped onto a fizzler, every second cube drop actually drops 2 cubes, meaning that if you deactivate the fizzler at the correct time, the test can suddenly become much simpler than it is supposed to be, having 2 rather than 1 cube to play around with... Both cubes are connected to the same dropper, so if you activate the dropper again, both cubes also fizzle to the new cube dropped...