I hope my point is clear 
When an automation envelope is used to control a parameter, it makes one calculation for each row. When the used speed is low, or with a sensitive parameter, there are steps or clicks audible. It would be nice if there were some smoothing option so that the output of the envelope is calculated with a finer resolution. I guess we lost the old “ticks” of the tracker engine, but once per tick would be sufficient in most situations.
this should not happen on rendered WAVs. by the way, the ticks are not lost: you can use F2xx command to set the number of ticks, or use the song properties entry to set it globally for the song.