Quasar flickering light.

Hey everyone, I recently bought the space fx pack form Aidy Burrows and Gleb Alex. and it seems that the quasar that they show in the videa does not have the flickering light that is in the product they show in the Video teaser. For reference here s the link
https://www.youtube.com/watch?v=3g8XxmqSP90 look through 0:48-0:55. Does anyone know how to create this effect?