That was it , having different settings per snapshot, even though they are not being used is an issue -- thanks so much -- switching between and Interstate and a Rockerverb -- in newest version 3.15 -- loud pop. It was that when I was going to the clean (Interstate), it was changing the Rockerverb volume behind the scene even though it was not in use -- then when I switch back to crunch (Rockerverb ) it was switch the Rockerverb volume parameters back -- and that was the pop. Once I set