Hi!
It’s extremely hard to tell unless I see the problem.
I believe this might be an example of Flash of unstyled content. It basically happens when the browser parses the HTML faster, than loading the CSS files, and it displays the content unstyled for a split second. I believe some solutions exist to this issue, but it’s not plugin related.
I might be wrong though. If you have an url to look at, then I might be able to tell more.