When I use any of the Essential FX effect on an FX bus, I get pops and drop outs and overall bad performance. Even just clicking in the timeline with nothing playing I hear some subtle glitches and pops ( probably only audible with headphones).
We need more information - otherwise we are just guessing what the issue is.
Please read this topic and come back with your computer specification - details required are in the linked to topic - a MediaInfo analysis of one of the source video clips showing this issue.
. . . . Essential FX . . . .
Do you mean New Blue Video Essentials 3 and/or 4, and is it all effects or particular effects that are causing this issue?