I think it's infulent by three aspects:
1.we should keep the atomizer moist ,if the liquid is used out,it may smelling a little burnt taste,because it works like this :liquid flow to atomizer by line(which material can bear high temperature),when you smoke ,the heating wire are trun red,so ,if there is no liquid ,it only can burn the lines,so smelling burnt.If the liquid is enough ,i think it will much better
2.The liquid quality is too bad ,i think bad liquid of course lead to bad smelling.
3.Maybe we should smoking one mouth,then ,after 5 seconds,we begin the second,because if we don't have any stop but continuous,it means the heating wire still burning.
4.Maybe also infulent by the structure in side.Different design maybe have different questions,may be we should find a good desing in side,For easy change the liquild to smoking .