autothrottle
GreatC:
If by "autothrottle sampling" you are referring to the speed continuing to increase as you come down final you will find it is a design feature.
In gusts and on approach the autothrottle gradually increases the speed which is being maintained to aid in avoiding speeds going much below Vref. Despite what you have bugged, the autothrottle will acquire and maintain anything up to 20 knots above that speed depending on the size of the gusts.
If you are wondering why they are so gun-shy of a low speed state on landing have a look at your FCTM and see what your tail clearance is if you touch down at Vref-15. If memory serves it's about 12 inches........