I just got a Mac, I switched over from my PC and never had this issue using Studio One on my PC. I have two tracks, one of the instrumental I imported, and another for voice. I want to record voice, and I usually click that little record symbol that's to the left of the track name in that little box with a few track options. (the button next to the one that looks like a little speaker). It just won't let me click it. It usually lights up red when it is clicked, but when I click it, nothing happens. I've never had a problem clicking it before. On my old laptop to record voice, I would click that mini record button, then click the main record button on the Bottom to record. Never had a problem. Why isn't it letting me click it so that I can record?