Play Pause Stop All Grayed Out

I’m sure I’m just missing an obvious UI feature, but I find that when I copy from one project, paste to a second project, and then return to the first project, I am unable to playback the original project. I have all my options available. I can navigate. I can edit. But Play, Pause, and Stop are all grayed out, the spacebar has no effect, and I can’t figure out how to get back into to “playback mode”. Feel like it must be an obvious fix that I’m missing… Thanks!

You’ve probably still got the first project in play, record, or pause mode. “Stop” the playback in the first project and play should be available in the other.