I know you're thinking this is probably user error, but I find that the loop button sometimes activates without me clicking it. I am using Studio One Professional v 188.8.131.52992. To be clear, I am talking about the oval shaped button immediately to the right of the record button at the bottom of the screen. I have never experienced it deactivating without me clicking it - but it certainly sometimes gets activated without me clicking it. Any one else experiencing this?