This is because you are running an older copy of the Capo demo that you still have on your Mac. Let’s fix that!
Using Spotlight at the top-right of your screen, search for “Capo kind:app”. Then, click the ‘Show All’ item in the list.
At this point, you have two options:
You can identify which of these results is the demo version by launching all of them, and verifying that there is no “Purchase…” or “License…” items in the application menu (i.e. the Capo item in the main menu).
This is the better option when there are many results to sift through. Follow these steps to ensure you only have the version of Capo from the Mac App Store:
Now you should have only one copy of Capo on your machine—the one you purchased!