Hi @lgoeser
The bubbles and dripping observed after dispense are almost certainly due to over aspiration of air for lower volume aliquots.
If the volume variability range was lower than 400uL you could increase the air transport volume for dispense but this will be too much to solve via liquid class parameters.
Are the volumes known prior to loading? If so I would use a worklist and aspirate variable volumes. If not, I would determine an estimated volume prior to aspiration by detecting liquid level relative to the bottom of the container and calculate volume based on container geometry. See a couple of relevant threads linked below:
Thanks.
-Nick