The aim of this paper is to study the effect of the speed of capsule filling and the inherent machine vibrations on fill weight for a dosator-nozzle machine. The results show that increasing speed of capsule filling amplifies the vibration intensity (as measured by Laser Doppler vibrometer) of the machine frame, which leads to powder densification. The mass of the powder (fill weight) collected via the nozzle is significantly larger at a higher capsule filling speed. Therefore, there is a correlation between powder densification under more intense vibrations and larger fill weights. Quality-by Design of powder based products should evaluate the effect of environmental vibrations on material attributes, which in turn may affect product quality.