Popping sound in ARC, sub mini, rears mostly with changing movies, previews--came after latest update.

After years of having Sonos, this latest update (applied it today to my Sonos App)---I now have the Sonos Pop--this was something I'd read about in and out for the past 5 years. Sure I powered down, reset the TV---but for now---switch a TV channel (pop like little squeek), change previews --same sound, change streaming service--same sound. Gratefully once a source is playing and engaged--no pop but here it is.