Transitions not always smooth in Customizr's slider

Hi, I am using Customizr (with a child theme) on this site and overall it’s working great. However, a few visitors have told me that in the Home page slider, the transition from one slide to the next is sometimes not a smooth fade.

Is there anything I can do in Customizr’s settings or CSS or other code to ensure smooth-fading transitions between all slides on my site?

BTW, I noticed that this ticket (about another slide-transition issue) that Giorgio25b mentions something about JS blocking the page source code as a possible source of slide-transition problems.