GarageBand and the PreSonus Audiobox GO

Also, this looks like everything he walked me through: If GarageBand isn't working on your Mac - Apple Support

So if you try all that yourself and none of it works, you can tell that to the support rep to save yourself about 45 minutes of time on the phone. I imagine they’d bump your right up to the next level of support.

I still haven’t solved it, but I’ll tell you two things that might be helpful.

1. I was pleasantly surprised to find I could quickly get on a call with Apple for GarageBand support. I hadn’t even bothered to look to see if that was an option because I assumed I wouldn’t be (or if it was it wouldn’t be any good). It was a long call, and the tier 1 support guy wasn’t able to figure it out. (They have another level of support but I didn’t have time to continue.)
2. One of the things he had me try was to use GarageBand on another user profile. I created another profile with a different name and password (don’t know if that’s important or not but it’s what he told me to do) and skipped all the things I could skip (e.g., I didn’t connect an Apple ID). Everything worked fine on this new profile.

So, at least in my case, I can use this interface the way I wanted to. I just can’t use it on my usual profile (yet).

If you have a chance to get on the phone with support, I’d recommend it. If the tier 1 agent can’t figure it out, I bet the next level can.

And please let me know if you get to the bottom of it!

It also works on GarageBand for my iPad. What's the difference between GarageBand for my iPad vs my MacBook that allows it to work on one and not the other?